SIP Operation

National Grid PLC
09 November 2007

National Grid plc ('NG')



9th November 2007



Notification of Directors' Interests



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NG SHARE INCENTIVE PLAN (the 'SIP')



Under the SIP scheme, operated through Towers Perrin Share Plan Services Limited
as Trustee, employees may acquire NG ordinary shares by regular monthly
contributions.  The current monthly purchase of 28,708 NG ordinary shares under
the scheme was confirmed by the Trustee yesterday, the shares having been
purchased in the market on 7th November, at a price of 797.5 pence per share, on
behalf of some 2,500 participants.



The following executive Directors of NG are beneficiaries of the number of
shares purchased on their behalf:


Director                       Shares purchased in SIP
Mark Fairbairn                 16 Ordinary Shares
Steven Holliday                16 Ordinary Shares





The Directors total interests after these events are:


Director                             Resulting total interest
Mark Fairbairn                       319,719 Ordinary Shares
Steven Holliday                      717,054 Ordinary Shares



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Contact: D C Forward, Assistant Secretary- (0207 004 3226)


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