Transaction in Own Shares

National Grid PLC
12 February 2007

National Grid plc announces that on 7 February 2007 it purchased for
cancellation 235,000 of its ordinary shares at a price of 780.3749 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 2,713,138,732.
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