Director/PDMR Shareholding

National Grid PLC
02 January 2007



2nd January 2007


National Grid plc (NG.)
Notification of Directors' Interests on Appointment

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Following his appointment as a Director on 1 January 2007, NG notifies that the
interests of Mark Fairbairn (previously a senior group employee, and a current
Director of National Grid Gas Holdings plc), are as follows:

Interests in NG shares on appointment

Beneficially owned ordinary shares: 20,495.

Executive Share options:

Number                         Option Price           Exercise period
8,649                          375.75p                June 2001 to June 2008
2,180                          435.75p                July 2002 to July 2009
33,489                         531.5p                 June 2003 to June 2010
31,152                         481.5p                 June 2005 to June 2012



Sharematch Scheme Marching Awards:

(Exercisable at nil cost, subject to retention of originally purchased shares
in trust until exercise).

Number                                        Exercise period

4,897                                         May 2007 to May 2014
2,134                                         June 2008 to June 2015



Performance Share Plan Awards:

Number                                        Release, subject to performance 
                                              criteria, on
47,072                                        8 June 2008
40,225                                        28 June 2009
40,572                                        27 June 2010



Deferred Share plan

Number                                        Transfer on
10,800                                        15 June 2009



Employee Sharesave Scheme Options:

Number                Exercise price            Exercise period
833                   397p                      6 months from 1 September 2007
862                   383p                      6 months from 1 April 2010
1,760                 558p                      6 months from 1 April 2012


Total share interests on appointment: 245,120- ordinary shares
                                      6,132- 'B' shares

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






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