National Storage Mechanism | Additional information

1 March 2023

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

Voting Rights update

National Grid's registered capital as of 28 February 2023 consisted of 3,930,371,661 ordinary shares, of which, 253,958,934 were held as treasury shares; leaving a balance of 3,676,412,727 with voting rights.

The figure of 3,676,412,727 may be used by shareholders as the denominator for the calculations by which they will determine if they are required to notify their interest in, or a change to their interest in, National Grid under the FCA's Disclosure Guidance and Transparency Rules.

Pritti Patel

General Counsel, Corporate and Deputy Company Secretary

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