Total Voting Rights

3 April 2018

National Grid plc (National Grid)

Voting Rights and Capital Update

National Grid's registered capital as at 31 March 2018 consisted of 3,637,747,827 ordinary shares, of which 282,960,111 were held as treasury shares; leaving a balance of 3,354,787,716 shares with voting rights.

The figure of 3,354,787,716 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 Disclosure and Transparency Rules.

Contact: C James, Assistant Company Secretary, (0207 004 3116).