##### Table of Contents



SECURITIES AND EXCHANGE COMMISSION
 Washington, D.C. 20549
 FORM 20-F
  o
    
    REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934
 OR
 þ
    
    ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934For the fiscal year ended March 31, 2006
 OR
 o
    
    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
 OR
 o
    
    SHELL COMPANY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
 Date
of event requiring this shell company report..........
 For the transition period from   to
 Commission file number: 001-14958
 NATIONAL GRID PLC
  
 
 Securities registered or to be registered pursuant to Section 12(b) of the Securities Exchange
Act of 1934:
 Title of each class
    
    Name of each exchange on which registeredOrdinary Shares of 11 17/43 pence each
    
    The New York Stock Exchange*American Depositary Shares, each representing five
Ordinary Shares of 11 17/43 pence each
    
    The New York Stock Exchange
 *
    
    Not for trading, but only in connection with the registration of American Depositary Shares
representing Ordinary Shares pursuant to the requirements of the Securities and Exchange
Commission. Securities registered or to be registered pursuant to Section 12(g) of the Securities Exchange
Act of 1934:
 Securities for which there is a reporting obligation pursuant to Section 15(d) of the Securities
Exchange Act of 1934:
  Ordinary Shares of 11 17/43 pence each
    
    2,719,699,118
  þ o
  o þ
  þ o
  Large accelerated filer þ
    
    Accelerated filer o
    
    Non-accelerated filer o
  o þ
  o þ




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##### 



Cautionary Statement
   
  
 TABLE OF CONTENTS
  PART IItem 1. Identity of Directors, Senior Management and AdvisersItem 2. Offer Statistics and Expected TimetableItem 3. Key InformationItem 4. Information on the CompanyItem 4A. Unresolved Staff CommentsItem 5. Operating and Financial Review and ProspectsItem 6. Directors, Senior Management and EmployeesItem 7. Major Shareholders and Related Party TransactionsItem 8. Financial InformationItem 9. The Offer and ListingItem 10. Additional InformationItem 11. Quantitative and Qualitative Disclosures about Market RiskItem 12. Description of Securities Other than Equity SecuritiesPART IIItem 13. Defaults, Dividend Arrearages and DelinquenciesItem 14. Material Modifications to the Rights of Security Holders and Use of ProceedsItem 15. Controls and ProceduresItem 16. [Reserved]Item 16A. Audit committee financial expertItem 16B. Code of EthicsItem 16C. Principal Accountant Fees and ServicesItem 16D. Exemptions from the Listing Standards for Audit CommitteesItem 16E. Purchases of Equity Securities by the Issuer and Affiliated PurchasersPART IIIItem 17. Financial StatementsItem 18. Financial StatementsItem 19. ExhibitsSIGNATUREEX-1.3EX-2.B.1.1EX-2.B.1.2EX-2.B.1.3EX-2.B.1.4EX-2.B.1.5EX-2.B.1.6EX-2.B.2.1EX-2.B.2.2EX-2.B.2.3EX-4.AEX-4.C.7EX-4.C.8.2EX-4.C.9.2EX-4.C.16EX-8EX-12.1EX-12.2EX-13EX-15.1EX-15.2  
 PART I
 
 Item 1. Identity of Directors, Senior Management and Advisers
  
 Item 2. Offer Statistics and Expected Timetable
  
 Item 3. Key Information
  -2-




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##### Table of Contents



Selected financial data
 IFRS:
 Year ended 31 March
    
    
    
    2006
    
    
    2005Turnover
    
    £m
    
    
    9,193
    
    
    
    7,382Total operating profit
    
    £m
    
    
    2,439
    
    
    
    2,142Profit for the year from continuing operations
    
    £m
    
    
    1,217
    
    
    
    1,120Profit for the year
    
    £m
    
    
    3,850
    
    
    
    1,424Basic earnings per share from continuing operations
    
    pence
    
    
    42.8
    
    
    
    36.3Basic earnings per share
    
    pence
    
    
    135.6
    
    
    
    46.2Diluted earnings per share
    
    pence
    
    
    135.0
    
    
    
    46.0Number of shares  basic
    
    millions
    
    
    2,837
    
    
    
    3,082Number of shares  diluted
    
    millions
    
    
    2,851
    
    
    
    3,096Total assets
    
    £m
    
    
    25,924
    
    
    
    27,560Net assets
    
    £m
    
    
    3,493
    
    
    
    2,121Total parent company shareholders equity
    
    £m
    
    
    3,482
    
    
    
    2,111Dividends per ordinary share: paid during the year
    
    pence
    
    
    25.4
    
    
    
    20.37Dividends per ordinary share: approved or proposed during the year
    
    pence
    
    
    26.1
    
    
    
    23.70Dividends per ordinary share: paid during the year
    
    US$
    
    
    0.455
    
    
    
    0.381Dividends per ordinary share: approved or proposed during the year
    
    US$
    
    
    0.467
    
    
    
    0.443
 US GAAP:
 Year ended 31 March
    
    
    
    2006
    
    
    2005
    
    
    2004
    
    
    2003
    
    
    2002Turnover
    
    £m
    
    
    9,216
    
    
    
    7,424
    
    
    
    7,761
    
    
    
    6,741
    
    
    
    4,004Operating profit
    
    £m
    
    
    1,810
    
    
    
    1,804
    
    
    
    1,523
    
    
    
    1,386
    
    
    
    889Net income from continuing operations
    
    £m
    
    
    711
    
    
    
    1,037
    
    
    
    696
    
    
    
    562
    
    
    
    (166
    )Net income/(loss)
    
    £m
    
    
    1,307
    
    
    
    1,304
    
    
    
    998
    
    
    
    751
    
    
    
    (167
    )Basic earnings per share from continuing
operations
    
    pence
    
    
    26.2
    
    
    
    38.3
    
    
    
    25.8
    
    
    
    27.3
    
    
    
    (12.4
    )Basic earnings/(loss) per share
    
    pence
    
    
    48.2
    
    
    
    48.2
    
    
    
    37.0
    
    
    
    36.4
    
    
    
    (12.4
    )Diluted earnings per share
    
    pence
    
    
    48.0
    
    
    
    47.9
    
    
    
    36.9
    
    
    
    35.4
    
    
    
    (9.9
    )Number of shares  basic
    
    millions
    
    
    2,710
    
    
    
    2,705
    
    
    
    2,694
    
    
    
    2,060
    
    
    
    1,340Number of shares  diluted
    
    millions
    
    
    2,724
    
    
    
    2,719
    
    
    
    2,701
    
    
    
    2,166
    
    
    
    1,443Total assets
    
    £m
    
    
    32,287
    
    
    
    37,274
    
    
    
    35,347
    
    
    
    36,947
    
    
    
    17,727Net assets
    
    £m
    
    
    9,788
    
    
    
    10,629
    
    
    
    9,875
    
    
    
    9,515
    
    
    
    3,862Equity shareholders funds
    
    £m
    
    
    9,747
    
    
    
    10,591
    
    
    
    9,821
    
    
    
    9,426
    
    
    
    3,759Dividends per ordinary share: paid during the year
    
    pence
    
    
    25.4
    
    
    
    20.37
    
    
    
    18.25
    
    
    
    16.44
    
    
    
    15.49Dividends per ordinary share: approved or
proposed during the year
    
    pence
    
    
    26.1
    
    
    
    23.70
    
    
    
    19.78
    
    
    
    17.20
    
    
    
    16.04Dividends per ordinary share: paid during the year
    
    US$
    
    
    0.455
    
    
    
    0.381
    
    
    
    0.307
    
    
    
    0.261
    
    
    
    0.223Dividends per ordinary share: approved or
proposed during the year
    
    US$
    
    
    0.467
    
    
    
    0.443
    
    
    
    0.332
    
    
    
    0.273
    
    
    
    0.231
 -3-




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Exchange rates
   High
    
    LowJune 2006*
    
    
    1.8817
    
    
    
    1.8398May 2006
    
    
    1.8911
    
    
    
    1.8286April 2006
    
    
    1.8220
    
    
    
    1.7389March 20065
    
    
    1.7567
    
    
    
    1.7256February 2006
    
    
    1.7807
    
    
    
    1.7343January 2006
    
    
    1.7885
    
    
    
    1.7404December 2005
    
    
    1.7740
    
    
    
    1.7188
 average**2005/06
    
    
    1.782004/05
    
    
    1.852003/04
    
    
    1.702002/03
    
    
    1.552001/02
    
    
    1.44
 
 *
    
    For the period to 16 June 2006.**
    
    The average for each period is calculated by using the average of the exchange rates on the last
day of each month during the period. Risk
factors
 
 Item 4. Information on the Company
  Operating and Financial Review Note 36 Group undertakings and joint
ventures Glossary of
Terms Definitions
 Property, plant and equipment
 United Kingdom
  UK electricity and gas transmission
  -4-




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UK gas distribution
  National Grid Wireless.
 United States
  US electricity transmission
 US electricity and gas distribution
 -5-




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##### Table of Contents



Item 4A. Unresolved Staff Comments
  
 Item 5. Operating and Financial Review and Prospects
 Operating and Financial Review Research and development
 
 Item 6. Directors, Senior Management and Employees
 Board of Directors Directors Remuneration Report Note 9 Pensions and other post-retirement
benefits Corporate Governance Employee share
ownership Note 31 Share capital
  31
    
    
    Average
    
    
    Average
    
    
    AverageMarch
    
    
    fiscal
    
    
    fiscal
    
    
    fiscal2006
    
    
    2006
    
    
    2005
    
    
    2004UK
    
    
    11,409
    
    
    
    11,421
    
    
    
    11,784
    
    
    
    11,943US
    
    
    8,362
    
    
    
    8,414
    
    
    
    8,663
    
    
    
    9,402Rest of the World
    
    
    12
    
    
    
    8
    
    
    
    13
    
    
    
    10Continuing operations
    
    
    19,783
    
    
    
    19,843
    
    
    
    20,460
    
    
    
    21,355Discontinued operations
    
    
    
    
    
    
    686
    
    
    
    4,147
    
    
    
    4,303Total
    
    
    19,783
    
    
    
    20,529
    
    
    
    24,607
    
    
    
    25,658
 
 Item 7. Major Shareholders and Related Party Transactions
 Major shareholders
  Number of
    
    % of outstandingordinary shares
    
    share capital*The Capital Group Companies, Inc.
    
    
    158,845,806
    
    
    
    5.86Legal and General Investment Management Ltd
    
    
    114,673,601
    
    
    
    4.02Barclays
    
    
    104,940,379
    
    
    
    3.86Credit Suisse First Boston group
    
    
    92,446,121
    
    
    
    3.41
 
 *
    
    This number is calculated in relation to the issued share capital at the time the holding was
disclosed.     -6-




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Note 34
Related party transactions
 
 Item 8. Financial Information
 Group
Balance Sheet Group Income
Statement Group Statement
of Recognised Income and Expense Group Cash
Flow Statement Notes to
the Accounts Legal and related
matters Dividends
  
 Item 9. The Offer and Listing
 Price history
  Ordinary share (pence)
    
    ADS ($)High
    
    Low
    
    High
    
    Low2005/06
    
    
    613.50
    
    
    
    489.25
    
    
    
    53.45
    
    
    
    44.482004/05
    
    
    549.50
    
    
    
    421.25
    
    
    
    52.06
    
    
    
    37.592003/04
    
    
    438.00
    
    
    
    374.75
    
    
    
    41.45
    
    
    
    30.192002/03
    
    
    511.50
    
    
    
    365.75
    
    
    
    37.40
    
    
    
    26.692001/02
    
    
    581.00
    
    
    
    417.25
    
    
    
    41.75
    
    
    
    30.402005/06 Q4
    
    
    613.50
    
    
    
    551.00
    
    
    
    53.45
    
    
    
    48.69Q3
    
    
    573.50
    
    
    
    503.50
    
    
    
    49.85
    
    
    
    44.48Q2
    
    
    561.00
    
    
    
    511.00
    
    
    
    51.64
    
    
    
    45.20Q1
    
    
    550.75
    
    
    
    489.25
    
    
    
    50.72
    
    
    
    46.372004/05 Q4
    
    
    549.50
    
    
    
    486.75
    
    
    
    52.06
    
    
    
    45.71Q3
    
    
    496.00
    
    
    
    461.00
    
    
    
    48.02
    
    
    
    42.50Q2
    
    
    472.00
    
    
    
    423.50
    
    
    
    43.00
    
    
    
    39.17Q1
    
    
    436.50
    
    
    
    421.25
    
    
    
    40.55
    
    
    
    37.59June 2006*
    
    
    615.00
    
    
    
    584.00
    
    
    
    57.34
    
    
    
    53.34May 2006
    
    
    606.50
    
    
    
    552.00
    
    
    
    56.67
    
    
    
    51.93April 2006
    
    
    578.50
    
    
    
    556.50
    
    
    
    52.51
    
    
    
    48.83March 2006
    
    
    603.50
    
    
    
    570.00
    
    
    
    52.77
    
    
    
    49.50February 2006
    
    
    613.50
    
    
    
    578.00
    
    
    
    53.45
    
    
    
    50.49January 2006
    
    
    577.50
    
    
    
    551.00
    
    
    
    51.60
    
    
    
    48.69December 2005
    
    
    573.50
    
    
    
    541.50
    
    
    
    49.85
    
    
    
    47.10
 
 *
    
    For the period to 16 June 2006. -7-




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Markets
  
 Item 10. Additional Information
 Memorandum and Articles of Association
   General
  
    
    carrying on the business of a holding company;
 
    
    employing the funds of the Company to develop and expand its business; and
 
    
    carrying on any other activity supplemental to the foregoing or capable of enhancing the Companys profitability.
  Directors
      Rights, preferences and restrictions
   -8-




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Variation of Rights
  General Meetings
  Rights of Non-Residents
  Disclosure of interests
    -9-




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B Shares
     Material contracts
  -10-




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Exchange controls
  Taxation
  
    
    a citizen or resident of the United States,
    
    a corporation or other entity taxable as a corporation, created or organised under the
laws of the United States or any state thereof, or
    
    a trust or an estate the income of which is subject to US federal income tax without
regard to its source and that holds such shares or ADSs as capital assets.
     
    
    the US Internal Revenue Code of 1986, as amended (the Code) and regulations issued
thereunder, all of which are subject to change, possibly with retroactive effect, and in
part on
    
    the representation of The Bank of New York as depositary (the Depositary).
   -11-




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Taxation of dividends
    Taxation of capital gains
   
    
    a US citizen who is resident or ordinarily resident in the UK
    
    a US corporation which is resident in the UK by reason of its
business being managed and controlled in the UK
    
    a US citizen who is trading or carrying on a profession or
vocation in the UK and used, held or acquired ADSs or ordinary
shares for the purpose of such trade, profession or vocation
    
    a US corporation which is otherwise carrying on business through a
permanent establishment in the U.K. and used, held or acquired
ADSs or ordinary shares for the purpose of such permanent
establishment.
    -12-




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UK stamp duty and stamp duty reserve tax (SDRT)
   US information reporting and backup withholding
  UK inheritance tax
 Estate Tax
Convention
 Documents on display
  -13-




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Item 11. Quantitative and Qualitative Disclosures about Market Risk
 Treasury Policy Commodity contracts
 
 Item 12. Description of Securities Other than Equity Securities
  
 PART II
 
 Item 13. Defaults, Dividend Arrearages and Delinquencies
  
 Item 14. Material Modifications to the Rights of Security Holders and Use of Proceeds
  
 Item 15. Controls and Procedures
   
 Item 16. [Reserved]
 
 Item 16A. Audit committee financial expert
  
 Item 16B. Code of Ethics
  
 Item 16C. Principal Accountant Fees and Services
  Audit Fees
  -14-




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Audit-Related Fees
  Tax Fees
  All Other Fees
    
 Item 16D. Exemptions from the Listing Standards for Audit Committees
  
 Item 16E. Purchases of Equity Securities by the Issuer and Affiliated Purchasers
  
 PART III
 
 Item 17. Financial Statements
  
 Item 18. Financial Statements
 Statement of Directors Responsibilities for
Preparing the Accounts Group Accounting Policies Group Income
Statement Group Balance
Sheet Group Cash Flow
Statement Group Statement of Recognised Income and
Expense Notes to the
Accounts
  Report of Independent Registered Public Accounting Firm to the Board of Directors and Shareholders
of National Grid plc
  -15-




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Item 19. Exhibits
   Description1.1
    
    Memorandum and Articles of Association of National Grid Transco plc
(Exhibit 1 to National Grid Group Form 20-F dated 21 June 2002 File No.
1-14958).
    
    Incorporated by
reference1.2
    
    Amendment to Memorandum and Articles of Association of National Grid
Transco plc (Exhibit 1 to National Grid Transco Form 20-F dated 11 June
2003 File No. 1-14958).
    
    Incorporated by
reference1.3
    
    Articles of Association of National Grid plc adopted by Special
Resolution passed on 25 July 2005.
    
    Filed herewith2(a)
    
    Amended and restated Deposit Agreement dated as of 31 January 2002 (Exhibit 2(a) to National Grid Group Form 20-F dated 21 June 2002 File
No. 1-14958).
    
    Incorporated by reference
 -16-




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Description2(b).1.1
    
    Prospectus issued by National Grid plc and National Grid Electricity
Transmission plc on 18 August 2005 relating to 12,000,000
(previously 6,000,000,000)
issuable under the Euro Medium Term Note Programme.
    
    Filed herewith2(b).1.2
    
    Supplementary
Prospectus dated 26 August 2006.
    
    Filed herewith2(b).1.3
    
    Supplementary
Prospectus dated 17 November 2005.
    
    Filed herewith2(b).1.4
    
    Supplementary
Prospectus dated 6 March 2006.
    
    Filed herewith2(b).1.5
    
    Supplementary
Prospectus dated 12 May 2006.
    
    Filed herewith2(b).1.6
    
    Supplementary
Prospectus dated 19 May 2006.
    
    Filed herewith2(b).2.1
    
    Prospectus issued by National Grid Gas Holdings plc and National Grid
Gas plc on 24 February 2006 relating to 10,000,000,000 issuable
under the Euro Medium Term Note Programme.
    
    Filed herewith2(b).2.2
    
    Supplementary
Prospectus dated 6 March 2006.
    
    Filed herewith2(b).2.3
    
    Supplementary
Prospectus dated 22 May 2006.
    
    Filed herewith4(a)
    
    Agreement and Plan of Merger dated as of February 25, 2006 between
National Grid plc, National Grid US8 Inc. and KeySpan Corporation.
    
    Filed herewith4(c).1
    
    Service Agreement among The National Grid Group plc, National Grid
Company plc and Edward Astle dated 27 July 2001 (Exhibit 4.3 to
National Grid Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).2
    
    Service Agreement among The National Grid Group plc, National Grid
Company plc and Steven Holliday dated 6 March 2001 (Exhibit 4.4 to
National Grid Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).3
    
    Service Agreement among National Grid Transco plc, National Grid USA
and Michael E. Jesanis dated 8 July 2004 (Exhibit 4.5 to National Grid
Transco Form 20-F dated 15 June 2005 File No. 1-14958).
    
    Incorporated by
reference4(c).4
    
    Service Agreement among National Grid Group plc, National Grid Company
plc and Steve Lucas dated 13 June 2002 (Exhibit 4.5 to National Grid
Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).5
    
    Service Agreement among The National Grid Group plc, National Grid
Company plc and Roger J. Urwin dated as of 17 November 1995 (Exhibit
4.7 to National Grid Transco Form 20-F dated 16 June 2004 File No.
1-14958).
    
    Incorporated by
reference4(c).6
    
    Service Agreement among National Grid Transco plc, National Grid
Company plc and Nicholas Winser dated 28 April 2003 (Exhibit 4.8 to
National Grid Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).7
    
    Changes to
Directors remuneration.
    
    Filed herewith4(c).8.1
    
    Letter of Appointment  John Allan (Exhibit 4.10 to National Grid
Transco Form 20-F dated 15 June 2005 File No. 1-14958).
    
    Incorporated by
reference4(c).8.2
    
    Letter dated 7 March 2006 to John Allan relating to appointment as
chairman of Remuneration Committee.
    
    Filed herewith4(c).9.1
    
    Letter of Appointment  John Grant (Exhibit 4.9 to National Grid
Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).9.2
    
    Letter dated 7 March 2006 to John Grant relating to retirement as
chairman of Remuneration Committee.
    
    Filed herewith4(c).10
    
    Letter of Appointment  Ken Harvey (Exhibit 4.10 to National Grid
Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).11
    
    Letter of Appointment  Paul Joskow (Exhibit 4.11 to National Grid
Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).12
    
    Letter of Appointment  Sir John Parker (Exhibit 4.12 to National Grid
Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference
 -17-




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Description4(c).13
    
    Letter of Appointment  Stephen Pettit (Exhibit 4.13 to National Grid
Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).14
    
    Letter of Appointment  Maria Richter (Exhibit 4.14 to National Grid
Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).15
    
    Letter of Appointment  George Rose (Exhibit 4.15 to National Grid
Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).16
    
    National Grid plc Deferred Share Plan.
    
    Filed herewith4(c).17
    
    National Grid Executive Share Option Plan 2002 (Exhibit 4(c) to
National Grid Group Form 20-F dated 21 June 2002 File No. 1-14958).
    
    Incorporated by
reference4(c).18
    
    National Grid Group Share Matching Plan 2002 (Exhibit 4(c) to National
Grid Group Form 20-F dated 21 June 2002 File No. 1-14958).
    
    Incorporated by
reference4(c).19
    
    National Grid Transco Performance Share Plan 2002 (as approved 23 July
2002 by a resolution of the shareholders of National Grid Group plc,
adopted 17 October 2002 by a resolution of the Board of National Grid
Group plc, amended 26 June 2003 by the Share Schemes Sub-Committee of
National Grid Transco plc, and amended 5 May 2004 by the Share Schemes
Sub-Committee of National Grid Transco plc) (Exhibit 4.19 to National
Grid Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference4(c).20
    
    National Grid Executive Share Option Plan 2000 (Exhibit 4C to National
Grid Group S-8 dated 26 July 2001 File No. 333-65968).
    
    Incorporated by
reference4(c).21
    
    National Grid Executive Share Option Scheme (Exhibit 4D to National
Grid Group S-8 dated 26 July 2001 File No. 333-65968).
    
    Incorporated by
reference4(c).22
    
    Lattice Long Term Incentive Scheme (Exhibit 4(c)(vi) to National Grid
Transco 20-F dated 11 June 2003 File No. 1-14958).
    
    Incorporated by
reference4(c).23
    
    Lattice Group Short Term Incentive Scheme (approved by a resolution of
the shareholders of BG Group plc effective 23 October 2000; approved by
a resolution of the Board of National Grid Transco plc on 30 April
2004; amended by resolutions of the Board of Lattice Group plc
effective on 21 October 2002 and 13 May 2004) (Exhibit 4.23 to National
Grid Transco Form 20-F dated 16 June 2004 File No. 1-14958).
    
    Incorporated by
reference6
    
    Earnings per share: The information set forth under the heading Note
14 Earnings per share on page 122 of the Companys Annual Report and
Accounts 2005/06 contained in Exhibit 15.1 is incorporated herein by
reference.
    
    Incorporated by
reference8
    
    List of subsidiaries.
    
    Filed herewith12.1
    
    Certification of Roger Urwin.
    
    Filed herewith12.2
    
    Certification of Steve Lucas.
    
    Filed herewith13
    
    Certifications of Roger Urwin and Steve Lucas furnished pursuant to 18
U.S.C. Section 1350.
    
    Filed herewith15.1
    
    National Grid plc Annual Report and Accounts 2005/06, in extracted form.
    
    Filed herewith15.2
    
    Consent of PricewaterhouseCoopers LLP, independent registered public
accounting firm to National Grid plc.
    
    Filed herewith
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##### Table of Contents



SIGNATURE
  NATIONAL GRID PLCBy:
    /s/  Steve LucasSteve LucasGroup Finance Director   -19-