Transaction in Own Shares

National Grid PLC
18 July 2007


National Grid plc - Transaction in Own Shares

18 July 2007


National Grid plc announces that on 17 July 2007 it purchased for cancellation
1,596,000 of its ordinary shares at a price of 702.49 pence per share from
Deutsche Bank AG London Branch.

Following the purchase and upon cancellation of these shares, the number of
ordinary shares with voting rights in issue (excluding Treasury shares) will be
2,646,545,955 and the number of ordinary shares in Treasury will be 13,919,121.

End




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