Director/PDMR Shareholding

National Grid PLC
10 September 2007

National Grid plc ('NG')

10th September 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 32,096 NG ordinary shares under
the scheme was confirmed by the Trustee late Friday 7th September, the shares
having been purchased in the market on 7th September, at a price of 732.0 pence
per share, on behalf of some 2,600 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                 17 Ordinary Shares
Steven Holliday                17 Ordinary Shares


The Directors total interests after these events are:

Director                             Resulting total interest
Mark Fairbairn                       319,173 Ordinary Shares

                                     B Shares- 6,132- unchanged
Steven Holliday                      717,022 Ordinary Shares

                                     Nil- B shares - unchanged



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Contact: R Kerner, Assistant Secretary- Share Schemes (0207 004 3223)


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