SIP Operation

National Grid PLC
07 February 2006

National Grid plc (NG)



7 February 2006

NG SHARE INCENTIVE PLAN (the 'SIP')



(Notification of Directors' Interests, pursuant to Section 324(2) of the
Companies Act 1985)



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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 41,873 NG ordinary shares under
the scheme was confirmed by the Trustee today, the shares having been purchased
in the market on 7 February 2006, at a price of 580.56 pence per share, on
behalf of some 2,700 participants.



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


Director               Shares purchased in SIP       Resulting total interest
Steven Holliday        22 Ordinary Shares            559,447 Ordinary Shares
Roger Urwin            22 Ordinary Shares            1,501,175 Ordinary Shares
                                                     281,977 B Shares- unchanged



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


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