Outcome of audit tender process

11 December 2025

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

Outcome of audit tender process

National Grid announces that, following the conclusion of a formal competitive audit tender process led by the Audit & Risk Committee, the Board has approved the proposed re-appointment of Deloitte LLP ("Deloitte") as external auditor to take effect from, and including, the financial year ending 31 March 2028. The re-appointment is subject to shareholder approval at the 2027 Annual General Meeting. Deloitte will continue as the Company's external auditor for the financial years ending 31 March 2026 and, subject to shareholder approval at the 2026 Annual General Meeting, 31 March 2027.

In line with the UK Statutory Audit Services for Large Companies Market Investigation (Mandatory Use of Competitive Tender Processes and Audit Committee Responsibilities) Order 2014, the Company is required to tender the statutory audit every 10 years and rotate every 20 years. The Company initially appointed Deloitte as the statutory auditor with effect from the year ending 31 March 2018.

Information on the audit tender process will be included in the Company's 2026 Annual Report and Accounts.

Julian Baddeley

Group Company Secretary