Transaction in Own Shares

National Grid PLC
14 March 2008

National Grid plc - Transaction in Own Shares

14 March 2008

National Grid plc announces that on 13 March 2008 it purchased 377,700 of its
ordinary shares at a price of 712.6891 pence per share from Morgan Stanley
Securities Limited. The purchased shares will be held as Treasury shares.

Following the purchase of these shares, the number of ordinary shares with
voting rights in issue (excluding Treasury shares) will be 2,518,502,106 and the
number of ordinary shares in Treasury will be 63,411,410.


End



                      This information is provided by RNS
            The company news service from the London Stock Exchange