Holding(s) in Company

National Grid plc (NG.)

15th July 2011

Notification of Major Interest in NG. Ordinary Shares

NG today received a further notification from Crescent Holding GmbH, over total return equity swaps.

The relevant transactions have been in place for a number of years and (as required by changes made to DTR5) were initially notified in June 2009.

This notification is merely as a result of the extension, on 15 July 2011, of the existing position to 20 July 2012 over 149,414,285 NG ordinary shares (4.25% of the voting share capital).

This notice is given in fulfillment of National Grid plc's obligation under the DTR requirements.