Total Voting Rights

2 March 2015

National Grid plc (National Grid)

Voting Rights and Capital Update

National Grid's registered capital as at 28 February 2015 consisted of 3,891,691,900 ordinary shares, of which, 152,970,767 were held as treasury shares; leaving a balance of 3,738,721,133 shares with voting rights.

The figure of 3,738,721,133 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: A Morgan, Assistant Company Secretary, (0207 004 3228).