Total Voting Rights

3 April 2017

National Grid plc (National Grid)

Voting Rights and Capital Update

National Grid's registered capital as at 31 March 2017 consisted of 3,942,983,447 ordinary shares, of which, 193,119,878 were held as treasury shares; leaving a balance of 3,749,863,569 shares with voting rights.

The figure of 3,749,863,569 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, Company Secretarial Assistant, (0207 004 3116).