Directors' Share Interests

Monday 18 June 2012

National Grid plc (National Grid)

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Directors' Share Interests____________________________________________________________

Tom King, Executive Director, received confirmation on Friday from his broker following the sale in the US on 13 June 2012 of a total of 4,000 National Grid ADSs at $51.13 per share, in order to rebalance his portfolio following the recent release of shares from a maturing share award. He retains a total interest in 267,067 National Grid plc ADSs after this event.

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Contact: D C Forward, Assistant Secretary

0207 004 3226