Transaction in Own Shares

National Grid PLC
12 February 2007

National Grid plc announces that on 9 February 2007 it purchased for
cancellation 200,000 of its ordinary shares at a price of 791.0247 pence per 
share.



Following the purchase and upon the cancellation of these shares, the number of
ordinary shares with voting rights in issue will be 2,712,938,732.
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