Director/PDMR Shareholding

National Grid PLC
14 March 2006

14 March 2006

National Grid plc (NG)

Director's Interests in NG Ordinary Shares
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The Company has today received confirmation of the following dealings by Nick
Winser:

National Grid Executive Share Option Scheme

On 13th March, Nick Winser exercised Executive Share Scheme options granted to
him in June 1998 (10,633 shares; option price 375.75p per share) and June 1999
(47,236 shares; option price 455.25p per share) which were all sold on that day
at 601.5p per share;

On 14th March, he exercised Executive Share Scheme options granted to him in
June 2002 (37,383 shares; option price 481.5p per share) of which 21,184 shares
were sold on that day at 598p per share; and he retains 16,199 NG shares.

National Grid Share Matching Plan

In addition, on 14th March, the Trustee of the National Grid 1996 Employee
Benefit Trust (ESOP) confirmed that 2,509 shares were transferred to Nick Winser
on exercising the Sharematch award (at a total exercise price of £1) granted to
him under the National Grid Share Matching Scheme operation in 2002. These
shares are also retained by him.

(Note: For Companies Act purposes, certain Executive Directors of NG

(E Astle, S Holliday, R Urwin and N Winser) are deemed to have a technical
interest in all the shares held by the ESOP, together with all participating
employees. The joint interest ceases on those shares on transfer to individual
participants by the exercise of executive share options or under another
employees' share scheme.)

Nick Winser's total interest after this event is over 355,895 option/award
shares and 56,687 beneficially held NG ordinary shares.

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


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