Director/PDMR Shareholding

National Grid PLC
02 September 2005

National Grid plc ('NG')



2 September 2005



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





Following the implementation of the Return of Cash to Shareholders (further
details of which are contained in the Circular to Shareholders dated 6 June
2005) and the admission of New Ordinary Shares and B Shares in National Grid plc
to the Official List on 1 August 2005, the interests of the Directors of NG in
the shares of NG have changed.  Executive Directors' options under share schemes
remain unchanged.



We have been notified of the following revised interests following the Return of
Cash to Shareholders:


Director                           New Ordinary Shares                 B Shares

                                   (Nominal Value 1117/43p)            (Nominal Value 10p)
Executive Directors:
Edward Astle                       26,036                              0
Steve Holliday                     27,880                              0
Mike Jesanis                       3,121                               0
Steve Lucas                        97,139                              318
Roger Urwin                        247,447                             281,977
Nick Winser                        37,979                              11,978
Non-executive Directors:
John Allan                         Unchanged at 2,000                  0
John Grant                         8,775                               0
Ken Harvey                         3,399                               3,874
Paul Joskow                        4,385                               0
Sir John Parker                    45,832                              0
Stephen Pettit                     2,632                               0
Maria Richter                      1,755                               0
George Rose                        4,409                               5,025



In addition to the interests above and those options under share schemes in
which they are interested, certain of the Executive Directors are, for Companies
Act purposes, deemed to be technically interested in NG New Ordinary Shares and
B Shares held by various of the share scheme trusts as follows:


Shares held by                      Executive Directors deemed          Notes
                                    technically interested
The National Grid Group QUEST       Edward Astle                        The interest ceases as and when
Trustee Company Limited as trustee                                      shares are transferred to
for the National Grid Group plc     Steve Holliday                      participants who exercise their
Qualifying Employee Share Ownership                                     Sharesave scheme options.
Trust (the 'Quest')                 Steve Lucas

                                    Roger Urwin

                                    Nick Winser

Towers Perrin Share Plan Services   Edward Astle                        The interest ceases as and when
(Guernsey) Limited as trustee for                                       shares are transferred to
the National Grid Transco 1996      Steve Holliday                      participants who exercise their
Employee Benefit Trust                                                  options under the Share Matching
                                    Roger Urwin                         Scheme or the Executive Share
                                                                        Option Plan.
                                    Nick Winser

Towers Perrin Share Plan Services   Edward Astle                        The interest ceases as and when
Limited as trustee for the National                                     shares are transferred to
Grid Transco plc Share Incentive    Steve Holliday                      participants pursuant to the rules
Plan (the 'SIP')                                                        of the SIP.
                                    Steve Lucas

                                    Roger Urwin

                                    Nick Winser

Mourant & Co. Trustees as trustee   Steve Lucas                         The interest ceases as and when
of the Lattice Group Employees                                          shares are transferred to
Share Trust                                                             participants pursuant to the rules
                                                                        of the Lattice Group Long Term
                                                                        Incentive Scheme.

Lattice Group Trustees Limited as   Steve Lucas                         The interest ceases as and when
trustee of the Lattice Group                                            shares are transferred to
Employee Share Ownership Trust                                          participants pursuant to the rules
                                                                        of the Lattice Group Short Term
                                                                        Incentive Scheme.

Towers Perrin Share Plan Services   Edward Astle                        The interest ceases as and when
(Guernsey) Limited as trustee for                                       shares are transferred to
the National Grid Transco Group     Steve Holliday                      participants who exercise their
Employee Share Trust                                                    options under the Share Matching
                                    Steve Lucas                         Scheme or pursuant to the rules of
                                                                        the Performance Share Plan.
                                    Roger Urwin

                                    Nick Winser



Contact:  Richard Eves [phone]

Helen Richardson [phone]


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