Director/PDMR Shareholding

National Grid PLC
24 April 2008

National Grid plc (NG.)

24 April 2008

Directors Interests in Shares - B Shares Conversion

Subsequent to the conversion of all outstanding former National Grid 'B' shares,
Ken Harvey has received confirmation from his investment manager of the
resulting ordinary share interest.

Director         Number of B Shares         Additional Ordinary      Resulting total interest in
                 Converted                  Share Interest           NG.Ordinary shares
                 
K Harvey         3,874                      341                      3,740


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Contact:
D C Forward
Assistant Secretary
0207 004 3226


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