INVESTMENT OBJECTIVE

The investment objective of the Fund is to seek high current income and preservation of capital through investments in high quality, short-term, liquid securities. These securities are commonly known as money market instruments.

FEES AND EXPENSES

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Example

PRINCIPAL INVESTMENT STRATEGIES

PRINCIPAL RISKS

PERFORMANCE

The bar chart and table below provide some indication of the risks of investing in the Fund by illustrating the variability of the Fund’s returns. The performance information reflects the impact of the Fund’s voluntary expense limitation in effect during a portion of the periods shown. If Lord Abbett had not agreed to limit expenses, returns would have been lower. Each assumes reinvestment of dividends

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and distributions. The Fund’s past performance is not necessarily an indication of how the Fund will perform in the future.

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MANAGEMENT

Investment Adviser. The Fund’s investment adviser is Lord, Abbett & Co. LLC (“Lord Abbett”).

PURCHASE AND SALE OF FUND SHARES

The minimum initial and additional amounts shown below vary depending on the class of shares you buy and the type of account. Certain financial intermediaries may impose different restrictions than those described below. Class I shares are only available for purchase by Lord Abbett and its affiliates, including Lord Abbett sponsored employee benefit plans. See ‘‘Choosing a Share Class – Investment Minimums’’ in the prospectus for more information.

You may sell (redeem) shares through your securities broker, financial professional or financial intermediary on any business day the Fund calculates its net asset value (‘‘NAV’’). If you have direct account access privileges, you may redeem your shares by contacting the Fund in writing at Lord Abbett Funds Service Center, P.O. Box 534489, Pittsburgh, PA 15253-4489 (regular mail) or Attention: 534489, 500 Ross Street 154-0520, Pittsburgh, PA 15262 (overnight mail), by calling 888-522-2388 or by accessing your account online at www.lordabbett.com.

TAX INFORMATION

The Fund’s distributions, if any, generally are taxable to you as ordinary income, unless you are a tax-exempt investor or investing through a tax-advantaged

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arrangement, such as a 401(k) plan or an IRA. Any withdrawals from such a tax-advantaged arrangement may be taxable to you.

PAYMENTS TO BROKER-DEALERS AND OTHER FINANCIAL INTERMEDIARIES

If you purchase Fund shares through a broker-dealer or other financial intermediary (such as a bank), the Fund and the Fund’s distributor or its affiliates may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other financial intermediary and your individual financial professional to recommend the Fund over another investment. Ask your individual financial professional or visit your financial intermediary’s website for more information.

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INVESTMENT OBJECTIVE

The investment objective of the Fund is to seek high current income and preservation of capital through investments in high quality, short-term, liquid securities. These securities are commonly known as money market instruments.

PRINCIPAL INVESTMENT STRATEGIES

The Fund is a money market fund that attempts to manage its portfolio to maintain a stable share price of $1.00 in accordance with applicable rules of the SEC. The Fund has adopted a policy to invest 99.5% or more of its total assets in cash, U.S. Government securities, and/or repurchase agreements that are collateralized fully (i.e., collateralized by cash and/or U.S. Government securities) in order to qualify as a ‘‘government money market fund’’ under Rule 2a-7 under the 1940 Act.

To pursue its objective, under normal conditions, the Fund invests at least 80% of its net assets in:

· U.S. Treasuries;

· Debt issued by Ginnie Mae;

· Debt issued by government sponsored enterprises including, but not limited to, the FHLBanks, Fannie Mae, Freddie Mac, and the Federal Farm Credit Banks; and

· Repurchase agreements collateralized by the securities listed above.

The Fund will provide shareholders with at least 60 days’ notice of any change in this policy.

The Fund, like all other money market funds, is subject to the diversity, liquidity, credit quality, maturity, and other requirements of Rule 2a-7 under the 1940 Act.

As a ‘‘government money market fund’’ under Rule 2a-7, the Fund will (1) be permitted to use the amortized cost method of valuation to seek to maintain a $1.00 share price and (2) not be subject to the discretionary or mandatory liquidity fee on Fund redemptions which might apply to other types of funds in the future should certain triggering events specified in Rule 2a-7 occur. The Board has reserved its ability to change this policy with respect to discretionary liquidity fees, but such change would only become effective after the Fund's disclosure has been updated to reflect its new policy. In addition, if the Fund is experiencing a negative gross yield as a result of negative interest rates, the Fund may be able to either convert from a stable share price to a floating share price or reduce the number of shares outstanding (e.g., through a reverse stock split) to maintain a stable net asset value per share, subject to certain Board determinations and disclosures to shareholders.

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The Fund seeks to remain fully invested in accordance with its investment objective. In response to adverse economic, market, or other unfavorable conditions, or to meet regulatorily-imposed liquidity requirements, however, the Fund may temporarily invest its assets in cash in a defensive manner. The Fund also may increase its investments in cash in unusual circumstances, such as unusually large cash inflows (whether through the purchase of Fund shares or the sale of securities) or anticipated increases in redemptions. Although the Fund seeks to be fully invested, to the extent that the Fund invests in cash, the Fund may not achieve its investment objective.

The Fund may sell a security if it no longer meets the Fund’s investment criteria or for a variety of other reasons, such as to comply with SEC requirements regarding the quality, maturity, duration, and diversification of the Fund’s portfolio, to secure gains, limit losses, increase cash, or satisfy redemption requests, among others. In considering whether to sell a security, the Fund may evaluate factors including, but not limited to, the condition of the economy, changes in the issuer’s financial condition, changes in the outlook for the issuer’s industry, the Fund’s valuation target for the security, and the impact of the security’s duration on the Fund’s overall duration.

Lord Abbett is registered with the U.S. Commodity Futures Trading Commission as a commodity pool operator (“CPO”) under the Commodity Exchange Act (“CEA”).  However, with respect to the Fund, Lord Abbett has filed a claim of exclusion from the definition of the term CPO and therefore, Lord Abbett is not subject to registration or regulation as a pool operator under the CEA with respect to the Fund.

PRINCIPAL RISKS

In addition to the risks of overall market movements and risks that are specific to an individual security, the principal risks you assume when investing in the Fund are described below. The Fund attempts to manage these risks through careful security selection and continual portfolio review and analysis, but there can be no assurance or guarantee that these strategies will be successful in reducing risk. Please see the statement of additional information (‘‘SAI’’) for a further discussion of strategies employed by the Fund and the risks associated with an investment in the Fund.

· Interest Rate Risk: A rise in prevailing interest rates generally will cause the price of a fixed rate debt security to fall. Generally, the longer the maturity of a security or weighted average maturity of the Fund, the more sensitive its price is to a rise in interest rates. The Fund’s yield may vary in response to changes in interest rates and other market factors. During periods when the Fund holds low-yielding securities, the Fund may have little or no net investment income and the Fund’s yield may decline substantially. A wide variety of market factors can cause interest rates to rise, including central bank monetary policy, rising inflation, and changes in general economic conditions. Periods of low interest rates increase the exposure of bond investors to the risks associated with rising interest rates.

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· Credit Risk: Many securities in which the Fund invests are not supported by the full faith and credit of the U.S. Government, even though they are issued by government sponsored enterprises. This means that the U.S. Government is not legally required to pay principal and interest to the Fund when these securities mature. For example, Ginnie Mae securities are backed by the full faith and credit of the U.S. Government, while Fannie Mae, Freddie Mac, Farmer Mac, FHLBank, and Federal Farm Credit Banks securities are not. There can be no assurance that the U.S. Government will provide financial support to government sponsored enterprises if it is not legally required to do so. In these situations, the Fund is exposed to the credit risk of the issuing government sponsored enterprise, which may fail to make timely payments of principal or interest, or may default on such payments.

· Mortgage-Related Securities Risk: Mortgage-related securities issued by government sponsored enterprises may be particularly sensitive to changes in prevailing interest rates and economic conditions, including delinquencies and defaults. The prices of mortgage-related securities, depending on their structure and the rate of payments, can be volatile. Like other debt securities, when interest rates rise, the value of mortgage-related securities generally will decline; however, when interest rates are declining, the value of mortgage- related securities with prepayment features may not increase as much as other fixed income securities. Alternatively, rising interest rates may cause prepayments to occur at a slower-than-expected rate, extending the duration of a security and typically reducing its value. Early repayment of principal on some mortgage-related securities may deprive the Fund of income payments above current market rates. The payment rate thus will affect the price and volatility of a mortgage-related security. The value of some mortgage-related securities may fluctuate in response to the market’s perception of the creditworthiness of the government sponsored enterprises that issue them.

· Issuer Concentration Risk: Because the Fund may invest most of its assets in securities issued or guaranteed by a small number of government sponsored enterprises that are not backed by the full faith and credit of the U.S. Government, it may be more exposed to developments affecting an individual government sponsored enterprise than a fund that invests more widely.

· Repurchase Agreement Risk: If the other party to a repurchase agreement defaults on its obligation under the agreement, the Fund may suffer delays and incur costs or lose money in exercising its rights under the agreement, or may be prevented from exercising such rights. If the seller fails to repurchase the security and the market value of the security declines, the Fund will lose money.

· Money Market Fund Regulatory Risk: Money market funds and the securities they invest in are subject to comprehensive regulations. The enactment of new legislation or regulations, as well as changes in interpretation and enforcement of current laws, may affect the manner of operation, performance and/or yield of money market funds. The SEC has adopted amendments to money market fund

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regulation that, among other things, increase the daily and weekly liquid asset requirements; require certain money market funds to impose discretionary and mandatory liquidity fees; and permit government money market funds (such as the Fund), that are experiencing a negative gross yield as a result of negative interest rates, to either convert from a stable share price to a floating share price or reduce the number of shares outstanding (e.g., through a reverse stock split) to maintain a stable net asset value per share, subject to certain Board determinations and disclosures to shareholders. The Fund's operations will be impacted as it comes into compliance with the new regulations.

· Portfolio Management Risk: The strategies used and investments selected by the Fund’s portfolio management team may fail to produce the intended result and the Fund may not achieve its objective. The securities selected for the Fund may not perform as well as other securities that were not selected for the Fund. As a result, the Fund may suffer losses or underperform other funds with the same investment objective or strategies, and may generate losses even in a favorable market.

You could lose money by investing in the Fund. Although the Fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the Fund is not insured or guaranteed by the FDIC or any other government agency. The Fund’s sponsor is not required to reimburse the Fund for losses, and you should not expect that the sponsor will provide financial support to the Fund at any time, including during periods of market stress.

ADDITIONAL INFORMATION ABOUT INVESTMENT AND OPERATIONAL RISKS

In addition to the principal investment risks described above, the Fund may also be subject to other investment and operational risks, including:

· Cyber Security Risk: As the use of technology has become more prevalent in the course of business, Lord Abbett and other service providers have become more susceptible to operational and information security risks. Cyber incidents can result from deliberate attacks or unintentional events and include, but are not limited to, gaining unauthorized access to electronic systems for purposes of misappropriating assets, personally identifiable information (“PII”) or proprietary information (e.g., trading models and algorithms), corrupting data, or causing operational disruption, for example, by compromising trading systems or accounting platforms. Other ways in which the business operations of Lord Abbett, other service providers, or issuers of securities in which Lord Abbett invests a shareholder’s assets may be impacted include interference with a shareholder’s ability to value its portfolio, the unauthorized release of PII or confidential information, and violations of applicable privacy, recordkeeping and other laws. A shareholder and/or its account could be negatively impacted as a result.

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While Lord Abbett has established internal risk management security protocols designed to identify, protect against, detect, respond to and recover from cyber security incidents, there are inherent limitations in such protocols including the possibility that certain threats and vulnerabilities have not been identified or made public due to the evolving nature of cyber security threats. Furthermore, Lord Abbett cannot control the cyber security systems of third-party service providers or issuers. Any problems relating to the performance and effectiveness of security procedures used by the Fund or its service providers to protect the Fund’s assets, such as algorithms, codes, passwords, multiple signature systems, encryption and telephone call-backs, may have an adverse impact on the Fund or its investors. Furthermore, as the Fund’s assets grow, it may become a more appealing target for cybersecurity threats such as hackers and malware. There currently is no insurance policy available to cover all of the potential risks associated with cyber incidents. Unless specifically agreed by Lord Abbett separately or required by law, Lord Abbett is not a guarantor against, or obligor for, any damages resulting from a cyber security-related incident.

· Large Shareholder Risk: To the extent a large number of shares of the Fund is held by a single shareholder or group of related shareholders (e.g., an institutional investor, another Lord Abbett Fund or multiple accounts advised by a common adviser) or a group of shareholders with a common investment strategy, the Fund is subject to the risk that a redemption by those shareholders of all or a large portion of their Fund shares will adversely affect the Fund’s performance by forcing the Fund to sell portfolio securities, potentially at disadvantageous prices, to raise the cash needed to satisfy the redemption request. In addition, the funds and other accounts over which Lord Abbett has investment discretion that invest in the Fund may not be limited in how often they may purchase or sell Fund shares. Certain Lord Abbett Funds or accounts may hold substantial percentages of the shares of the Fund, and asset allocation decisions by Lord Abbett may result in substantial redemptions from (or investments in) the Fund. These transactions may adversely affect the Fund’s performance to the extent that the Fund is required to sell investments (or invest cash) when it would not otherwise do so. Redemptions of a large number of shares also may increase transaction costs or, by necessitating a sale of portfolio securities, have adverse tax consequences for Fund shareholders. Additionally, redemptions by a large shareholder also potentially limit the use of any capital loss carryforwards and other losses to offset future realized capital gains (if any) and may limit or prevent the Fund’s use of tax equalization.

· Operational Risk: The Fund also is subject to the risk of loss as a result of other services provided by Lord Abbett and other service providers, including pricing, administrative, accounting, tax, legal, custody, transfer agency, and other services. Operational risk includes the possibility of loss caused by inadequate procedures and controls, human error, and system failures by a service provider, each of which may negatively affect the Fund’s performance. For example, trading delays or errors could prevent the Fund from benefiting

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from potential investment gains or avoiding losses. In addition, a service provider may be unable to provide an NAV for the Fund or share class on a timely basis. Similar types of operational risks also are present for issuers of securities in which the Fund invests, which could result in material adverse consequences for such issuers, and may cause the Fund’s investment in such securities to lose value.

· Business Continuity Risk: Lord Abbett has developed a Business Continuity Program (the “Program”) that is designed to minimize the disruption of normal business operations in the event of an adverse incident impacting Lord Abbett, its affiliates, or the Fund. While Lord Abbett believes that the Program should enable it to reestablish normal business operations in a timely manner in the event of an adverse incident, there are inherent limitations in such programs (including the possibility that contingencies have not been anticipated and procedures do not work as intended) and, under some circumstances, Lord Abbett, its affiliates, and any vendors used by Lord Abbett, its affiliates, or the Fund could be prevented or hindered from providing services to the Fund for extended periods of time. These circumstances may include, without limitation, acts of God, acts of governments, any act of declared or undeclared war or of a public enemy (including acts of terrorism), power shortages or failures, utility or communication failure or delays, labor disputes, strikes, shortages, supply shortages, system failures or malfunctions. The Fund’s ability to recover any losses or expenses it incurs as a result of a disruption of business operations may be limited by the liability, standard of care, and related provisions in its contractual arrangements with Lord Abbett and other service providers.

· Market Disruption and Geopolitical Risk: Geopolitical and other events (e.g., wars, terrorism, natural disasters, epidemics or pandemics) may disrupt securities markets and adversely affect global economies and markets, thereby decreasing the value of the Fund’s investments. Sudden or significant changes in the supply or prices of commodities or other economic inputs may have material and unexpected effects on both global securities markets and individual countries, regions, sectors, companies, or industries, which could significantly reduce the value of the Fund’s investments. Wars, terrorist attacks, natural disasters, epidemics or pandemics could result in unplanned or significant securities market closures or declines. Securities markets also may be susceptible to market manipulation or other fraudulent trading practices, which could disrupt the orderly functioning of markets, increase overall market volatility, or reduce the value of investments traded in them, including investments of the Fund. Instances of fraud and other deceptive practices committed by senior management of certain companies in which the Fund invests may undermine Lord Abbett’s due diligence efforts with respect to such companies, and if such fraud is discovered, negatively affect the value of the Fund’s investments. Financial fraud also may impact the rates or indices underlying the Fund’s investments.

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Raising the U.S. Government debt ceiling has become increasingly politicized. Any failure to increase the total amount that the U.S. Government is authorized to borrow could lead to a default on U.S. Government obligations. A default by the U.S. Government would be highly disruptive to the U.S. and global securities markets and could significantly reduce the value of the Fund’s investments. Similarly, political events within the United States at times have resulted, and may in the future result, in a shutdown of government services, which could adversely affect the U.S. economy, decrease the value of many Fund investments, and increase uncertainty in or impair the operation of the U.S. or other securities markets.

On January 31, 2020, the United Kingdom (“UK”) left the European Union (“EU”) (commonly known as “Brexit”). An agreement between the UK and the EU governing their future trade relationship became effective on January 1, 2021, but critical aspects of the relationship remain unresolved and subject to further negotiation and agreement. Brexit has resulted in volatility in European and global markets and could have negative long-term impacts on financial markets in the UK and throughout Europe. There is still considerable uncertainty relating to the potential consequences of the exit, how the negotiations for new trade agreements will be conducted, and whether the UK’s exit will increase the likelihood of other countries also departing the EU. Any further exits from the EU, or the possibility of such exits, or the abandonment of the euro, the common currency of the EU, may cause additional market disruption globally and introduce new legal and regulatory uncertainties.

Substantial government interventions (e.g., currency controls) also could adversely affect the Fund. War, terrorism, economic uncertainty, and related geopolitical events have led, and in the future may lead, to increased short-term market volatility and may have adverse long-term effects on U.S. and world economies and markets generally. Likewise, sanctions threatened or imposed by jurisdictions, including the United States, against a country or entities or individuals in another country (such as sanctions imposed against Russia, Russian entities and Russian individuals in connection with Russia’s invasion of Ukraine in 2022) may impair the value and liquidity of securities issued by issuers in such country and may result in the Fund using fair valuation procedures to value such securities. Even if the Fund does not have significant investments in Russian securities, sanctions, or the threat of sanctions (including any Russian retaliatory responses to such sanctions), may cause volatility in regional and global markets and may negatively impact the performance of various sectors and industries, as well as companies in other countries, including through global supply chain disruptions, increased inflationary pressures and reduced economic activity, which could have a negative effect on the performance of the Fund. Furthermore, if after investing in the Fund an investor is included on a sanctions list, the Fund may be required to cease any further dealings with the investor’s interest in the Fund until such sanctions are lifted or a license is sought under applicable law to continue dealings. Although Lord

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Abbett expends significant effort to comply with the sanctions regimes in the countries where it operates, one of these rules could be violated by Lord Abbett’s or the Fund's activities or investors, which would adversely affect the Fund.

In addition, natural and environmental disasters, (e.g., earthquakes, tsunamis, hurricanes), epidemics or pandemics, and systemic market dislocations such as those occurring in connection with the 2008 Global Financial Crisis, have been highly disruptive to economies and markets, adversely affecting individual companies and industries, securities markets, interest rates, credit ratings, inflation, investor sentiment, and other factors affecting the value of the Fund’s investments. During such market disruptions, the Fund’s exposure to the risks described elsewhere in the “Principal Risks” section of the prospectus will likely increase. Market disruptions and sudden government interventions can also prevent the Fund from implementing its investment strategies and achieving its investment objective. To the extent the Fund has focused its investments in the stock index of a particular region, adverse geopolitical and other events in that region could have a disproportionate impact on the Fund.

In March 2023, the shut-down of certain financial institutions raised economic concerns over disruption in the U.S. banking system. There can be no certainty that the actions taken by the U.S. government to strengthen public confidence in the U.S. banking system will be effective in mitigating the effects of financial institution failures on the economy and restoring public confidence in the U.S. banking system. Other adverse developments that affect financial institutions or the financial services industry generally, or concerns or rumors about any events of these kinds or other similar risks, may reduce liquidity in the market generally or have other adverse effects on the economy, the Fund or issuers in which the Fund invests. In addition, issuers in which the Fund invests and the Fund may not be able to identify all potential solvency or stress concerns with respect to a financial institution or to transfer assets from one bank or financial institution to another in a timely manner in the event such bank or financial institution comes under stress or fails.

The impact of the COVID-19 outbreak, and the effects of other infectious illness outbreaks, epidemics, or pandemics, may be short term or may continue for an extended period of time. For example, a global pandemic or other widespread health crises could negatively affect the global economy, the economies of individual countries, and the financial performance of individual issuers, sectors, industries, asset classes, and markets in significant and unforeseen ways. Health crises caused by outbreaks of disease may also exacerbate other pre-existing political, social, and economic risks in certain countries or globally. The foregoing could disrupt the operations of the Fund and its service providers, adversely affect the value and liquidity of the Fund’s investments, and negatively impact the Fund’s performance and your investment in the Fund.

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· Valuation Risk: The valuation of the Fund’s investments involves subjective judgment. There can be no assurance that the Fund will value its investments in a manner that accurately reflects their current market values or that the Fund will be able to sell any investment at a price equal to the valuation ascribed to that investment for purposes of calculating the Fund’s NAV. Incorrect valuations of the Fund’s portfolio holdings could result in the Fund’s shareholder transactions being effected at an NAV that does not accurately reflect the underlying value of the Fund’s portfolio, resulting in the dilution of shareholder interests.

DISCLOSURE OF PORTFOLIO HOLDINGS

A description of the Fund’s policies and procedures regarding the disclosure of the Fund’s portfolio holdings is available in the SAI. Further information is available at www.lordabbett.com.

The Fund will disclose on Lord Abbett’s website, within five business days after the end of each month, a schedule of portfolio holdings and information regarding the Fund. This information will be posted at www.lordabbett.com. In addition, the Fund will file with the SEC on Form N-MFP, within five business days after the end of each month, more detailed portfolio holdings information. The Fund’s Forms N-MFP will be available on the SEC’s website and Lord Abbett’s website also will contain a link to these filings, when available. Lord Abbett’s website also will disclose the following information for the Fund as of the end of each business day for the previous six months: (1) the percentage of the Fund’s total assets invested in daily and weekly liquid assets; (2) the Fund’s daily net inflows and outflows; and (3) the Fund’s current market-based NAV per share.

MANAGEMENT AND ORGANIZATION OF THE FUND

Board of Directors. The Board oversees the management of the business and affairs of the Fund. The Board appoints officers who are responsible for the day-to-day operations of the Fund and who execute policies authorized by the Board. At least 75 percent of the Board members are not “interested persons” (as defined in the 1940 Act) of the Fund.

Investment Adviser. The Fund’s investment adviser is Lord Abbett, which is located at 90 Hudson Street, Jersey City, NJ 07302-3973. Founded in 1929, Lord Abbett manages one of the nation’s oldest mutual fund complexes and manages approximately $185.2 billion in assets across a full range of mutual funds, institutional accounts, and separately managed accounts, including $1.0 billion for which Lord Abbett provides investment models to managed account sponsors as of September 30, 2023.

Management Fee. Lord Abbett is entitled to a management fee of 0.15% based on the Fund’s average daily net assets.

For the fiscal year ended June 30, 2023, the effective annual rate of the management fee paid to Lord Abbett was 0.15% of the Fund’s average daily net assets.

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In addition, Lord Abbett provides certain administrative services to the Fund pursuant to an Administrative Services Agreement in return for a fee at an annual rate of 0.04% of the Fund’s average daily net assets. The Fund pays all of its expenses not expressly assumed by Lord Abbett.

Each year the Board considers whether to approve the continuation of the existing management and administrative services agreements between the Fund and Lord Abbett. A discussion regarding the basis for the Board’s approval is available in the Fund’s annual report to shareholders for the fiscal year ended June 30^th.

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CHOOSING A SHARE CLASS

Each class of shares represents an investment in the same portfolio of securities, but each has different expenses, eligibility requirements, dividends, and yields. Class A or C shares purchased directly are not subject to any front-end sales charge or a CDSC. However, Class A or C shares initially purchased without a front-end sales charge and subsequently exchanged for shares of another Lord Abbett Fund are subject to any applicable front-end sales charge and Class A or C shares acquired by exchange from another Lord Abbett Fund are subject to any applicable CDSC, as described below.

You may purchase shares at the NAV per share next determined after we receive your purchase order submitted in good order. You should read this section carefully to determine which class of shares is best for you and discuss your selection with your financial intermediary.

Key Features of Share Classes. The following table compares key features of each share class. You should review the fee table and example at the front of this prospectus carefully before choosing your share class. As a general matter, share classes with relatively lower expenses tend to have relatively higher dividends. Your financial intermediary can help you decide which class meets your goals. Not all share classes may be available for purchase in all states or available through your financial intermediary. Please check with your financial intermediary for more information about the availability of share classes. Your financial intermediary may receive different compensation depending upon which class you choose.

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Investment Minimums. The minimum initial and additional amounts shown below vary depending on the class of shares you buy and the type of account. Certain financial intermediaries may impose different restrictions than those described below. Consult your financial intermediary for more information. Class I shares are

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only available for purchase by Lord Abbett and its affiliates, including Lord Abbett sponsored employee benefit plans.

SALES CHARGES

Class A or C shares purchased directly are not subject to any front-end sales charge or CDSC. However, Class A or C shares initially purchased without a front-end sales charge, including shares of the Fund acquired from the reinvestment of dividends or capital gain distributions, and subsequently exchanged for shares of another Lord Abbett Fund are subject to any applicable front-end sales charge and Class A or C shares acquired by exchange from another Lord Abbett Fund are subject to any applicable CDSC.

Class A and C Share CDSC. If you acquire Class A or C shares of the Fund in exchange for Class A or C shares of another Lord Abbett Fund subject to a CDSC, and you redeem any of the Class A or C shares before the first day of the month in which the one-year anniversary of your purchase falls, a CDSC of 1.00% normally will be collected.

Class I Shares. Class I shares are not subject to a CDSC.

CDSC. Regardless of share class, the CDSC is not charged on shares acquired through reinvestment of dividends or capital gain distributions and is charged on the original purchase cost or the current market value of the shares at the time they are redeemed, whichever is lower. In addition, repayment of loans under certain retirement and benefit plans will constitute new sales for purposes of assessing the CDSC. To minimize the amount of any CDSC, the Fund redeems shares in the following order:

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1. shares acquired by reinvestment of dividends and capital gain distributions (always free of a CDSC);

2. shares held for one year or more (Class A and C); and

3. shares held before the first anniversary of their purchase (Class A and C).

SALES CHARGE WAIVERS

CDSC Waivers. The CDSC generally will not be assessed on the redemption of Class A or C shares under the circumstances listed in the table below. Documentation may be required and some limitations may apply. Certain other types of redemptions may qualify for a CDSC waiver.

Concurrent Sales. A broker-dealer may pay on behalf of an investor or reimburse an investor for a CDSC otherwise applicable in the case of transactions involving purchases through such broker-dealer where the investor concurrently is selling his or her holdings in Class C shares of the Fund and buying Class A shares of the Fund, provided that the purchases are related to the requirements of a settlement agreement that the broker-dealer entered into with a regulatory body relating to share class suitability.

Sales Charge Waivers on Transfers between Accounts. Class A shares can be purchased at NAV under the following circumstances:

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· Transfers of Lord Abbett Fund shares from an IRA or other qualified retirement plan account to a taxable account in connection with a required minimum distribution; or

· Transfers of Lord Abbett Fund shares held in a taxable account to an IRA or other qualified retirement plan account for the purpose of making a contribution to the IRA or other qualified retirement plan account.

A CDSC will not be imposed at the time of the transaction under such circumstances; instead, the date on which such shares were initially purchased will be used to calculate any applicable CDSC when the shares are redeemed.

FINANCIAL INTERMEDIARY COMPENSATION

As part of a plan for distributing shares, authorized financial intermediaries that sell the Fund’s shares and service its shareholder accounts receive sales and service compensation. Additionally, authorized financial intermediaries may charge a fee to effect transactions in Fund shares.

Sales compensation originates from sales charges that are paid directly by shareholders and 12b-1 distribution fees that are paid by the Fund out of share class assets. Service compensation originates from 12b-1 service fees. Because 12b-1 fees are paid on an ongoing basis, over time the payment of such fees will increase the cost of an investment in the Fund, which may be more than the cost of other types of sales charges. The Fund currently is not making 12b-1 fee payments with respect to Class A and C shares under its Rule 12b-1 plan because the Board has not authorized the activation of the 12b-1 fees for Class A and C shares.

Lord Abbett Distributor may pay 12b-1 fees to authorized financial intermediaries or use the fees for other distribution purposes, including revenue sharing. The amounts paid by the Fund need not be directly related to expenses. If Lord Abbett Distributor’s actual expenses exceed the fee paid to it, the Fund will not have to pay more than that fee. Conversely, if Lord Abbett Distributor’s expenses are less than the fee it receives, Lord Abbett Distributor will keep the excess amount of the fee.

Sales Activities. The Fund may use 12b-1 distribution fees to pay authorized financial intermediaries to finance any activity that primarily is intended to result in the sale of shares. Lord Abbett Distributor uses its portion of the distribution fees attributable to the shares of a particular class for activities that primarily are intended to result in the sale of shares of such class. These activities include, but are not limited to, printing of prospectuses and statements of additional information and reports for anyone other than existing shareholders, preparation and distribution of advertising and sales material, expenses of organizing and conducting sales seminars, additional payments to authorized financial intermediaries, maintenance of shareholder accounts, the cost necessary to provide distribution-related services or personnel, travel, office expenses, equipment and other allocable overhead.

Service Activities. Lord Abbett Distributor may pay 12b-1 service fees to authorized financial intermediaries for any activity that primarily is intended to result in

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personal service and/or the maintenance of shareholder accounts or certain retirement and benefit plans. Any portion of the service fees paid to Lord Abbett Distributor will be used to service and maintain shareholder accounts.

Revenue Sharing and Other Payments to Dealers and Financial Intermediaries. Lord Abbett (the term ‘‘Lord Abbett’’ in this section also refers to Lord Abbett Distributor unless the context requires otherwise) may make payments to certain financial intermediaries for marketing and distribution support activities. Lord Abbett makes these payments, at its own expense, out of its own resources (including revenues from advisory fees and 12b-1 fees), and without any additional costs to the Fund or the Fund’s shareholders.

These payments, which may include amounts that sometimes are referred to as ‘‘revenue sharing’’ payments, are in addition to the Fund’s fees and expenses described in this prospectus. In general, these payments are intended to compensate or reimburse financial intermediary firms for certain activities, including: promotion of sales of Fund shares, such as placing the Lord Abbett Family of Funds on a preferred list of fund families; making Fund shares available on certain platforms, programs, or trading venues; educating a financial intermediary firm’s sales force about the Lord Abbett Funds; providing services to shareholders; and various other promotional efforts and/or costs. The payments made to financial intermediaries may be used to cover costs and expenses related to these promotional efforts, including travel, lodging, entertainment, and meals, among other things. In addition, Lord Abbett may provide payments to a financial intermediary in connection with Lord Abbett’s participation in or support of conferences and other events sponsored, hosted, or organized by the financial intermediary. The aggregate amount of these payments may be substantial and may exceed the actual costs incurred by the financial intermediary in engaging in these promotional activities or services and the financial intermediary firm may realize a profit in connection with such activities or services.

Lord Abbett may make such payments on a fixed or variable basis based on Fund sales, assets, transactions processed, and/or accounts attributable to a financial intermediary, among other factors. Lord Abbett determines the amount of these payments in its sole discretion. In doing so, Lord Abbett may consider a number of factors, including: a financial intermediary’s sales, assets, and redemption rates; the nature and quality of any shareholder services provided by the financial intermediary; the quality and depth of the financial intermediary’s existing business relationships with Lord Abbett; the expected potential to expand such relationships; and the financial intermediary’s anticipated growth prospects. Not all financial intermediaries receive revenue sharing payments and the amount of revenue sharing payments may vary for different financial intermediaries. Lord Abbett may choose not to make payments in relation to certain of the Lord Abbett Funds or certain classes of shares of any particular Fund.

In some circumstances, these payments may create an incentive for a broker-dealer or its investment professionals to recommend or sell Fund shares to you. Lord

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Abbett may benefit from these payments to the extent the broker-dealers sell more Fund shares or retain more Fund shares in their clients’ accounts because Lord Abbett receives greater management and other fees as Fund assets increase. For more specific information about these payments, including revenue sharing arrangements, made to your broker-dealer or other financial intermediary and the conflicts of interest that may arise from such arrangements, please contact your investment professional. In addition, please see the SAI for more information regarding Lord Abbett’s revenue sharing arrangements with financial intermediaries.

Payments for Recordkeeping, Networking, and Other Services. In addition to the payments from Lord Abbett or Lord Abbett Distributor described above, from time to time, Lord Abbett and Lord Abbett Distributor may have other relationships with financial intermediaries relating to the provision of services to the Fund, such as providing omnibus account services or executing portfolio transactions for the Fund. The Fund generally may pay recordkeeping fees for services provided to plans where the account is a plan-level or fund-level omnibus account and plan participants have the ability to determine their investments in particular mutual funds. If your financial intermediary provides these services, Lord Abbett or the Fund may compensate the financial intermediary for these services. In addition, your financial intermediary may have other relationships with Lord Abbett or Lord Abbett Distributor that are not related to the Fund.

For example, the Lord Abbett Funds may enter into arrangements with and pay fees to financial intermediaries that provide recordkeeping or other subadministrative services to certain groups of investors in the Lord Abbett Funds, including participants in retirement and benefit plans, investors in mutual fund advisory programs, investors in variable insurance products and clients of financial intermediaries that operate in an omnibus environment (collectively, ‘‘Investors’’). The recordkeeping services typically include: (a) establishing and maintaining Investor accounts and records; (b) recording Investor account balances and changes thereto; (c) arranging for the wiring of funds; (d) providing statements to Investors; (e) furnishing proxy materials, periodic Lord Abbett Fund reports, prospectuses and other communications to Investors as required; (f) transmitting Investor transaction information; and (g) providing information in order to assist the Lord Abbett Funds in their compliance with state securities laws. The fees that the Lord Abbett Funds pay are designed to compensate financial intermediaries for such services.

The Lord Abbett Funds also may pay fees to broker-dealers for networking services. Networking services may include but are not limited to:

· establishing and maintaining individual accounts and records;

· providing client account statements; and

· providing 1099 forms and other tax statements.

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The networking fees that the Lord Abbett Funds pay to broker-dealers normally result in reduced fees paid by the Fund to the transfer agent, which otherwise would provide these services.

Financial intermediaries may charge additional fees or commissions other than those disclosed in this prospectus, such as a transaction based fee or other fee for its service, and may categorize and disclose these arrangements differently than described in the discussion above and in the SAI. You may ask your financial intermediary about any payments it receives from Lord Abbett or the Fund, as well as about fees and/or commissions it charges.

PURCHASES

Initial Purchases. Lord Abbett Distributor acts as an agent for the Fund to work with financial intermediaries that buy and sell shares of the Fund on behalf of their clients. Generally, Lord Abbett Distributor does not sell Fund shares directly to investors. Initial purchases of Fund shares may be made through any financial intermediary that has a sales agreement with Lord Abbett Distributor. Unless you are investing in the Fund through a retirement and benefit plan, fee-based program or other financial intermediary, you and your investment professional may fill out the application and send it to the Fund at the address below. To open an account through a retirement and benefit plan, fee-based program or other type of financial intermediary, you should contact your financial intermediary for instructions on opening an account.

Please do not send account applications or purchase, exchange, or redemption orders to Lord Abbett’s offices in Jersey City, NJ.

Any class of shares of the Fund may be acquired by exchange from shares of the same class of any other Lord Abbett Fund (except for Lord Abbett Credit Opportunities Fund and Lord Abbett Special Situations Income Fund). Class A, C, and I shares of the Fund may also be purchased directly.

Additional Purchases. You may make additional purchases of Fund shares by contacting your investment professional or financial intermediary. If you have direct account privileges with the Fund, you may make additional purchases by:

• Telephone. If you have established a bank account of record, you may purchase Fund shares by telephone. You or your investment professional should call the Fund at 888-522-2388.

• Online. If you have established a bank account of record, you may submit a request online to purchase Fund shares by accessing your account online.

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Please log onto www.lordabbett.com and enter your account information and personal identification data.

• Mail. You may submit a written request to purchase Fund shares by indicating the name(s) in which the account is registered, the Fund’s name, the class of shares, your account number, and the dollar amount you wish to purchase. Please include a check for the amount of the purchase, which may be subject to a sales charge. If purchasing Fund shares by mail, your purchase order will not be accepted or processed until such orders are received by the Lord Abbett Funds Service Center at P.O. Box 534489, Pittsburgh, PA 15253-4489 (regular mail) or Attention: 534489, 500 Ross Street 154-0520, Pittsburgh, PA 15262 (overnight mail).

• Wire. You may purchase Fund shares via wire by sending your purchase amount to: BNY Mellon, NA, routing number: 011001234, bank account number: 030600, FBO: BNY Mellon Investment Servicing (US) Inc. as Agent FBO Lord Abbett Consolidated, Ref: your account name, the complete name of the Fund and the class of shares you wish to purchase and your Lord Abbett account number.

Good Order. “Good order” generally means that your purchase request includes: (1) the name of the Fund; (2) the class of shares to be purchased; (3) the dollar amount of shares to be purchased; (4) your properly completed account application or investment stub; and (5) a check payable to the name of the Fund or a wire transfer received by the Fund. In addition, for your purchase request to be considered in good order, you must satisfy any eligibility criteria and minimum investment requirements applicable to the Fund and share class you are seeking to purchase. An initial purchase order submitted directly to the Fund, or the Fund’s authorized agent (or the agent’s designee), must contain: (1) an application completed in good order with all applicable requested information; and (2) payment by check or instructions to debit your checking account along with a canceled check containing account information. Additional purchase requests must include all required information and the proper form of payment (i.e., check or wired funds).

See “Account Services and Policies – Procedures Required by the USA PATRIOT Act” for more information.

Initial and additional purchases of Fund shares are executed at the NAV next determined after the Fund or the Fund’s authorized agent receives your purchase request in good order. The Fund reserves the right to modify, restrict or reject any purchase order (including exchanges). All purchase orders are subject to acceptance by the Fund.

Insufficient Funds. If you request a purchase and your bank account does not have sufficient funds to complete the transaction at the time it is presented to your bank, your requested transaction will be reversed and you will be subject to any and all losses, fees and expenses incurred by the Fund in connection with processing the

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insufficient funds transaction. The Fund reserves the right to liquidate all or a portion of your Fund shares to cover such losses, fees and expenses.

Non-U.S. Investors. The Lord Abbett Family of Funds are not offered to investors resident outside the United States. The Fund may, however, accept purchases from U.S. citizens resident outside the United States who meet applicable eligibility requirements and furnish any requested documentation.

EXCHANGES

You or your investment professional may instruct the Fund to exchange shares of any class for shares of the same class of any other Lord Abbett Fund (except for Lord Abbett Credit Opportunities Fund and Lord Abbett Special Situations Income Fund), provided that the fund shares to be acquired in the exchange are available to new investors in such other fund. For investors investing through retirement and benefit plans or fee-based programs, you should contact the financial intermediary that administers your plan or sponsors the fee-based program to request an exchange.

If you have direct account privileges with the Fund, you may request an exchange transaction by:

· Telephone. You or your investment professional should call the Fund at 888-522-2388.

· Online. You may submit a request online to exchange your Fund shares by accessing your account online. Please log onto www.lordabbett.com and enter your account information and personal identification data.

· Mail. You may submit a written request to exchange your Fund shares by indicating the name(s) in which the account is registered, the Fund’s name, the class of shares, your account number, the dollar amount or number of shares you wish to exchange, and the name(s) of the eligible fund(s) into which you wish to exchange your Fund shares. If submitting a written request to exchange Fund shares, your exchange request will not be processed until the Fund receives the request in good order at Lord Abbett Funds Service Center, P.O. Box 534489, Pittsburgh, PA 15253-4489 (regular mail) or Attention: 534489, 500 Ross Street 154-0520, Pittsburgh, PA 15262 (overnight mail).

The Fund may revoke the exchange privilege for all shareholders upon 60 days’ written notice. In addition, there are limitations on exchanging Fund shares for a different class of shares, and moving shares held in certain types of accounts to a different type of account or to a new account maintained by a financial intermediary. Please speak with your financial intermediary if you have any questions.

An exchange of Fund shares for shares of another Lord Abbett Fund will be treated as a sale of Fund shares and any gain on the transaction may be subject to federal income tax. The Lord Abbett Fund into which you are exchanging may impose sales charges and/or 12b-1 distribution and/or service fees depending on which share class

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you purchase. You should read the current prospectus for any Lord Abbett Fund into which you are exchanging.

REDEMPTIONS

You may redeem your Fund shares by contacting your investment professional or financial intermediary. For shareholders investing through retirement and benefit plans or fee-based programs, you should contact the financial intermediary that administers your plan or sponsors the fee-based program to redeem your shares. You may be required to provide the Fund with certain legal or other documents completed in good order before your redemption request will be processed.

If you have direct account privileges with the Fund, you may redeem your Fund shares by:

· Telephone. You may redeem $100,000 or less from your account by telephone. You or your representative should call the Fund at 888-522-2388.

· Online. You may submit a request online to redeem your Fund shares by accessing your account online. Please log onto www.lordabbett.com and enter your account information and personal identification data.

· Mail. You may submit a written request to redeem your Fund shares by indicating the name(s) in which the account is registered, the Fund’s name, your account number, and the dollar amount or number of shares you wish to redeem. If submitting a written request to redeem your shares, your redemption will not be processed until the Fund receives the request in good order at Lord Abbett Funds Service Center, P.O. Box 534489, Pittsburgh, PA 15253-4489 (regular mail) or Attention: 534489, 500 Ross Street 154-0520, Pittsburgh, PA 15262 (overnight mail).

· Checkwriting. You may write checks against your account for a minimum of $500 up to a maximum of $5 million. A check drawn on an account will be honored based only on those shares in the account on which the check is drawn. This method of redeeming shares is only available, however, if you have fully completed the application.

If the signer has any legal capacity (i.e., the authority of an individual to act on behalf of an entity or other person(s)), the signature and capacity must be guaranteed by an eligible guarantor. Certain other legal documentation may be required. For more information regarding proper documentation please call 888-522-2388.

· Redemptions by Wire. In order to receive the proceeds of redemptions by wire, the Fund’s transfer agent must have the wiring instructions on file. To verify that this feature is in place, call 888-522-2388. Minimum wire amount for redemptions is $1,000. Your wire redemption request must be received by the Fund before the close of the New York Stock Exchange (‘‘NYSE’’) for money to be wired on the next business day (or thereafter as permitted by law).

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Insufficient Account Value. If you request a redemption transaction for a specific amount and your account value at the time the transaction is processed is less than the requested redemption amount, the Fund will deem your request as a request to liquidate your entire account.

Redemption Payments. Redemptions of Fund shares are executed at the NAV next determined after the Fund or your financial intermediary receives your request in good order. Normally, redemption proceeds are paid within three (but no more than seven) days after your redemption request is received in good order. If you redeem shares that were recently purchased, the Fund may delay the payment of the redemption proceeds until your check, bank draft, electronic funds transfer or wire transfer has cleared, which may take several days. This process may take up to 15 calendar days for purchases by check to clear. The Fund may postpone payment for more than seven days or suspend redemptions (i) during any period that the NYSE is closed, or trading on the NYSE is restricted as determined by the SEC; (ii) during any period when an emergency exists as determined by the SEC as a result of which it is not practicable for the Fund to dispose of securities it owns, or fairly to determine the value of its assets; and/or (iii) for such other periods as the SEC may permit. As a money market fund, the Fund may permanently suspend redemptions in connection with a liquidation of the Fund.53611

If you have direct account access privileges, the redemption proceeds will be paid by electronic transfer via an automated clearing house deposit to your bank account on record with the Fund. If there is no bank account on record, your redemption proceeds normally will be paid by check payable to the registered account owner(s) and mailed to the address to which the account is registered.

You may request that your redemption proceeds of at least $1,000 be disbursed by wire to your bank account of record by contacting the Fund and requesting the redemption and wire transfer and providing the proper wiring instructions for your bank account of record.

The Fund generally will require that you provide a Medallion Signature Guarantee executed by an eligible issuer participating in the Securities Transfer Agents Medallion Program 2000 (STAMP2000) in the circumstances described below. You can obtain one from most banks or securities dealers. Please note that a notarized signature or signature guarantees from financial institutions that are not participating in STAMP2000 will not be accepted. A Medallion Signature Guarantee is designed to protect you from fraud.

· You request that redemption proceeds be made payable and disbursed to a bank account that does not have one of the account owners in the account registration unless you previously provided a Medallion Signature Guarantee for that bank account;

· The request is signed by you in your legal capacity to sign on behalf of another person or entity (i.e., on behalf of an estate);

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· You request a redemption check be mailed to an address not currently on file or you had an address change within the last 30 days;

· You request redemption proceeds to be payable to a bank account that is not currently on file or to a bank account of record that was added or changed within the last 30 days; for any purpose, including purchases, redemptions, ACH transfers, or wire transfers;

· The redemption proceeds total more than $100,000; or

· The Fund and its service providers identify patterns that raise concern about fraud or other activity that may be harmful to you.

Institutional investors eligible to purchase Class I shares may redeem shares in excess of $100,000 in accounts held directly with the Fund without a guaranteed signature, provided that the proceeds are payable to the bank account of record and the redemption request otherwise is in good order.

Liquidity Management. The Fund has implemented measures designed to enable it to pay redemption proceeds in a timely fashion while maintaining adequate liquidity. The Fund’s portfolio management team continually monitors portfolio liquidity and adjusts the Fund’s cash level based on portfolio composition, redemption rates, market conditions, and other relevant criteria. Under normal circumstances, the Fund’s portfolio management team may meet redemption requests and manage liquidity by selling portfolio securities. Under certain circumstances, including stressed market conditions, the Fund’s portfolio management team may meet redemption requests and manage liquidity by (i) borrowing from a bank under a line of credit or from another Lord Abbett Fund (to the extent permitted under any SEC exemptive relief and the Fund’s investment restrictions, in each case as stated in the Fund’s SAI and/or prospectus, as applicable), (ii) transacting in exchange-traded funds and/or derivatives, or (iii) paying redemption proceeds in kind, as discussed below. Despite the Fund’s reasonable best efforts, however, there can be no assurance that the Fund will manage liquidity successfully in all market environments. As a result, the Fund may not be able to pay redemption proceeds in a timely fashion because of unusual market conditions, an unusually high volume of redemption requests, or other factors.

Redemptions in Kind. The Fund reserves the right to pay redemption proceeds in whole or in part by distributing liquid securities from the Fund’s portfolio. It is not expected that the Fund would pay redemptions by an in kind distribution except in unusual and/or stressed circumstances. If the Fund pays redemption proceeds by distributing securities in kind, you could incur brokerage or other charges, and tax liability, and you will bear market risks until the distributed securities are converted into cash.

You should note that your purchase, exchange, and redemption requests may be subject to review and verification on an ongoing basis.

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ACCOUNT SERVICES AND POLICIES

Certain of the services and policies described below may not be available through certain financial intermediaries. Contact your financial intermediary for services and policies applicable to you.

Account Services

Automatic Services for Fund Investors. You may buy or sell shares automatically with the services described below. With each service, you select a schedule and amount, subject to certain restrictions. You may set up most of these services when filling out the application or by calling 888-522-2388.

Telephone and Online Purchases and Redemptions. Submitting transactions by telephone or online may be difficult during times of drastic economic or market changes or during other times when communications may be under unusual stress. When initiating a transaction by telephone or online, shareholders should be aware of the following considerations:

· Security. The Fund and its service providers employ verification and security measures for your protection. For your security, telephone and online transaction requests are recorded. You should note, however, that any person with access to your account and other personal information (including personal identification number) may be able to submit instructions by telephone or online. The Fund and its affiliates (including Lord Abbett and other funds for which Lord Abbett serves as investment adviser), directors/trustees, and officers will not be liable for any loss, liability, cost, or expense due to unauthorized or

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fraudulent instructions, provided reasonable procedures were employed to confirm that the instructions received were genuine.

· Online Confirmation. The Fund is not responsible for online transaction requests that may have been sent but not received in good order. Requested transactions received by the Fund in good order are confirmed at the completion of the order and your requested transaction will not be processed unless you receive the confirmation message.

· No Cancellations. You will be asked to verify the requested transaction and may cancel the request before it is submitted to the Fund. The Fund will not cancel a submitted transaction once it has been received (in good order) and is confirmed at the end of the telephonic or online transaction.

Householding. We have adopted a policy that allows us to send only one copy of the prospectus, proxy materials, annual report and semiannual report to certain shareholders residing at the same “household.” This reduces Fund expenses, which benefits you and other shareholders. If you need additional copies or do not want your mailings to be “householded,” please call us at 888-522-2388 or send a written request with your name, the name of your fund or funds, and your account number or numbers to Lord Abbett Funds Service Center, P.O. Box 534489, Pittsburgh, PA 15253-4489 (regular mail) or Attention: 534489, 500 Ross Street 154-0520, Pittsburgh, PA 15262 (overnight mail).

Account Statements. Every investor automatically receives quarterly account statements.

Account Changes. For any changes you need to make to your account, consult your investment professional or call the Fund at 888-522-2388.

Systematic Exchange. You or your investment professional can establish a schedule of exchanges between the same classes of any other Lord Abbett Fund, provided that the fund shares to be acquired in the exchange are available to new investors in such other fund.

Account Policies

Pricing of Fund Shares. Under normal circumstances, NAV per share is calculated each business day at the close of regular trading on the NYSE, normally 4:00 p.m. Eastern time, on each day on which the NYSE is open for trading. The most recent NAV per share for the Fund is available at www.lordabbett.com. Purchases and sales (including exchanges) of Fund shares are executed at the NAV (subject to any applicable sales charges) next determined after the Fund or the Fund’s authorized agent receives your order in good order. In the case of purchase, redemption, or exchange orders placed through your financial intermediary, when acting as the Fund’s authorized agent (or the agent’s designee), the Fund will be deemed to have received the order when the agent or designee receives the order in good order.

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Purchase and sale orders must be placed by the close of trading on the NYSE in order to receive that day’s NAV; orders placed after the close of trading on the NYSE will receive the next business day’s NAV. Fund shares will not be priced on holidays or other days when the NYSE is closed for trading. In the event the NYSE is closed on a day it normally would be open for business for any reason (including, but not limited to, technology problems or inclement weather), or the NYSE has an unscheduled early closing on a day it has opened for business, the Fund reserves the right to treat such day as a business day. In such cases, the Fund would accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day, so long as Lord Abbett believes there generally remains an adequate market to obtain reliable and accurate market quotations.

In calculating NAV, securities are valued at cost plus (minus) amortized discount (premium), if any, pursuant to regulatory requirements applicable to money market funds.

Frequent Trading Policy and Procedures. Excessive, short-term or market timing trading practices (‘‘frequent trading’’) have the potential to disrupt management of a fund, raise its expenses, and harm long-term shareholders in a variety of ways, or to exploit market movements or inefficiencies in the way a mutual fund prices its shares. The Fund’s Board has evaluated the risks of frequent trading activities by the Fund’s shareholders and has determined that because the Fund invests primarily in highly liquid, short-term debt instruments and was designed with the expectation that shareholders will not hold Fund shares as long-term investments, it is unlikely that frequent trading would negatively affect the Fund or its shareholders. As a result, the Fund’s Board has not adopted policies and procedures to detect or deter frequent trading in the Fund.

Other funds in the Lord Abbett Family of Funds have adopted policies and procedures that are designed to identify and prevent or stop frequent trading. If you plan to exchange your Fund shares for shares of another Lord Abbett Fund, please read the prospectus of the other fund.

Procedures Required by the USA PATRIOT Act. To help the government fight the funding of terrorism and money laundering activities, federal law requires all financial institutions, including the Fund, to obtain, verify, and record information that identifies each person who opens an account. What this means for you – when you open an account, we will ask for your name, address, date and place of organization or date of birth, and taxpayer identification number or Social Security number, and we may ask for other information that will allow us to identify you. We will ask for this information in the case of persons who will be signing on behalf of certain entities that will own the account. We also may ask for copies of documents. If we are unable to obtain the required information within a short period of time after you try to open an account, we will return your purchase order or account application. Your monies will not be invested until we have all required information. You also should know that we may verify your identity through the use of a database

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maintained by a third party or through other means. If we are unable to verify your identity, we may liquidate and close the account. This may result in adverse tax consequences. In addition, the Fund reserves the right to reject purchase orders or account applications accompanied by cash, cashier’s checks, money orders, bank drafts, traveler’s checks, and third party or double-endorsed checks, among others.

Small Account Closing Policy. The Fund has established a minimum account balance of $1,000. The Fund may redeem your account (without charging a CDSC) if the NAV of your account falls below $1,000. The Fund will provide you with at least 60 days’ prior written notice before doing so, during which time you may avoid involuntary redemption by making additional investments to satisfy the minimum account balance.

How to Protect Your Account from State Seizure. Under state law, mutual fund accounts can be considered “abandoned property.” The Fund may be required by state law to forfeit or pay abandoned property to the state government if you have not accessed your account for a period specified by the state of your domicile. Depending on the state, in most cases, a mutual fund account may be considered abandoned and forfeited to the state if the account owner has not initiated any activity in the account or contacted the fund company holding the account for as few as three or as many as five years. Because the Fund is legally required to send the state the assets of accounts that are considered “abandoned,” the Fund will not be liable to shareholders for good faith compliance with these state laws. If you invest in the Fund through a financial intermediary, we encourage you to contact the financial intermediary regarding applicable state abandoned property laws.

If you hold your account directly with the Fund (rather than through an intermediary), we strongly encourage you to contact us at least once each year. Below are ways in which you can assist us in safeguarding your Fund investments:

· Log into your account at www.lordabbett.com. Please note that, by contrast, simply visiting our public website will not constitute contact with us under state abandoned property rules; instead, an account login is required.

· Call our 24-hour automated service line at 888-522-2388 and use your Personal Identification Number (PIN). If you have never used this system, you will need your account number to establish a PIN.

· Call one of our customer service representatives at 888-522-2388 Monday through Friday from 8:00 am to 5:30 pm Eastern time. To establish contact with us under certain states’ abandoned property rules, you will need to provide your name, account number, and other identifying information.

· Promptly notify us if your name, address, or other account information changes.

· Promptly vote on proxy proposals related to any Lord Abbett Fund you hold.

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· Promptly take action on letters you receive in the mail from the Fund concerning account inactivity, outstanding dividend and redemption checks, and/or abandoned property and follow the directions in these letters.

Additional Information. This prospectus and the SAI do not purport to create any contractual obligations between the Fund and shareholders. Further, shareholders are not intended third-party beneficiaries of any contracts entered into by (or on behalf of) the Fund, including contracts with Lord Abbett or other parties who provide services to the Fund.

DISTRIBUTIONS AND TAXES

The Fund normally declares dividends from its net investment income daily (if any) and pays such dividends monthly. If the net investment income of a class is negative on any day, the Fund will not pay a dividend on the class on that day and may resume paying dividends only when, on a future date, the undistributed net investment income of the class is positive. The Fund pays distributions of short-term capital gains (if any) annually. The Fund does not expect to make any distributions of long-term capital gains to shareholders.

For U.S. federal income tax purposes, any distributions of dividends from net investment income and short-term capital gains are taxable as ordinary income to shareholders, other than tax-exempt shareholders and shareholders investing through tax-advantaged arrangements (including certain retirement and benefit plan shareholders, as discussed below), regardless of whether paid in cash or reinvested in additional Fund shares. Distributions will be reinvested in Fund shares unless you instruct the Fund to pay them to you in cash. Any gain resulting from a sale, redemption, or exchange of Fund shares generally will also be taxable to you as either short-term or long-term capital gain, depending upon how long you have held such shares.

An additional 3.8% Medicare contribution tax generally will be imposed on the net investment income of U.S. individuals, estates and trusts whose income exceeds certain threshold amounts. For this purpose, net investment income generally will include distributions from the Fund and capital gains attributable to the sale, redemption or exchange of Fund shares.

Shareholders that are exempt from U.S. federal income tax, such as retirement and benefit plans that are qualified under Section 401 of the Code, generally are not subject to U.S. federal income tax on Fund dividends or distributions or on sales or exchanges of Fund shares. However, distributions from a retirement and benefit plan or other tax-advantaged arrangement generally are taxable to recipients as ordinary income.

You must provide your Social Security number or other taxpayer identification number to the Fund along with certifications required by the Internal Revenue Service when you open an account. If you do not or the Fund is otherwise legally

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required to do so, the Fund will withhold a ‘‘backup withholding’’ tax from your distributions, sale proceeds, and any other taxable payments to you.

Certain tax reporting information concerning the tax treatment of Fund distributions will be provided to shareholders each year. Because everyone’s tax situation is unique, you should consult your tax advisor regarding the treatment of such distributions under the federal, state, local, and foreign tax rules that apply to you as well as the tax consequences of gains or losses from the sale, redemption, or exchange of your shares.

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FINANCIAL HIGHLIGHTS

These tables describe the Fund’s performance for the fiscal years indicated. “Total Return” shows how much your investment in the Fund would have increased or decreased during each year without considering the effects of sales loads and assuming you had reinvested all dividends and distributions. These Financial Highlights have been audited by Deloitte & Touche LLP, the Fund’s independent registered public accounting firm, in conjunction with their annual audit of the Fund’s financial statements. Financial statements and the report of the independent registered public accounting firm thereon appear in the most recent annual report to shareholders and are incorporated by reference in the SAI, which is available upon request. Certain information reflects financial results for a single Fund share. Financial Highlights are provided for each class of shares with operations during the fiscal years indicated and shares outstanding as of the end of the most recent fiscal year.

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FINANCIAL HIGHLIGHTS 

^(a) Calculated using average shares outstanding during the period.

^(b) Total return for classes A and C does not consider the effects of sales loads and assumes the reinvestment of all distributions. Total return for all other classes assumes the reinvestment of all distributions.

^(c) Includes net realized gain (loss) on investments.

^(d) Amount less than $0.01.

^(e) Includes capital gain distribution.

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FINANCIAL HIGHLIGHTS (CONCLUDED)

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Lord Abbett U.S. Government & Government Sponsored Enterprises Money Market Fund, Inc.