Total Voting Rights

1 March 2017

National Grid plc (National Grid)

Voting Rights and Capital Update

National Grid's registered capital as at 28 February 2017 consisted of 3,942,983,447 ordinary shares, of which, 193,499,444 were held as treasury shares; leaving a balance of 3,749,484,003 shares with voting rights.

The figure of 3,749,484,003 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).