Senior Independent Director & Committee Changes

21 September 2023

National Grid plc ('National Grid' or 'Company')

The Company today announces some changes to the role of Senior Independent Director and its Board Committees.

Further to the announcement on 17 May 2023 that Thérèse Esperdy would step down from the Board as a Non-Executive Director on 31 December 2023, Ian Livingston will succeed Thérèse as the Senior Independent Director effective as at 31 December 2023.

The following Committee changes will also take place on 1 October 2023:

· Thérèse Esperdy will step down as being Chair of the Finance Committee. Thérèse will remain a member of the Finance Committee until 31 December 2023;

· Ian Livingston will become Chair of the Finance Committee and step down as Chair of the Remuneration Committee. Ian will remain a member of the Remuneration Committee;

· Martha Wyrsch will become Chair of the Remuneration Committee; and

· Iain Mackay will become a member of the Finance Committee.

From 1 October 2023, the membership of each Board Committee is as follows:

Audit & Risk Committee:

Iain Mackay (Chair), Thérèse Esperdy, Liz Hewitt, Ian Livingston, Jonathan Silver

Finance Committee:

Ian Livingston (Chair), Andy Agg, Thérèse Esperdy, Liz Hewitt, Iain Mackay, John Pettigrew

People & Governance Committee:

Paula Rosput Reynolds (Chair), Thérèse Esperdy, Earl Shipp, Jonathan Silver, Tony Wood

Remuneration Committee:

Martha Wyrsch (Chair), Ian Livingston, Iain Mackay, Anne Robinson

Safety & Sustainability Committee:

Earl Shipp (Chair), Anne Robinson, Tony Wood, Martha Wyrsch

This announcement is made in accordance with Listing Rule 9.6.11.

Pritti Patel

General Counsel, Corporate and Deputy Company Secretary