Transaction in Own Shares

National Grid PLC
08 March 2007


National Grid plc announces that on 08 March 2007 it purchased for cancellation
350,000 of its ordinary shares at a price of 765.0475 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 2,705,882,769.
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