3 October 2018

National Grid plc ('National Grid' or 'NG')

British Transco International Finance B.V.

Publication of Annual Report and Accounts - Group Company With Listed Debt

In June 2018, in accordance with Listing Rule 9.6.1, National Grid confirmed it had issued its Annual Report to shareholders and had made it available for public inspection at the UK Listing Authority's document viewing facility - the National Storage Mechanism (NSM) - situated at:

www.morningstar.co.uk/uk/NSM

We confirm that the Annual Report in respect of British Transco International Finance B.V., a NG Group subsidiary company with listed bonds, has been issued to shareholders.

In accordance with Listing Rule 17.3.1, we confirm that a copy of the above Annual Report has also been submitted to and will shortly be available for public inspection at the NSM.

The above document is also available electronically on the NG website at:

www.nationalgrid.com

Contact: Alice Parker, Senior Assistant Company Secretary (020 7004 3228)