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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 20-F

(Mark One)
£REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934
OR
RANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended 31 March 2024
OR
£TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
OR
£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
(Exact name of Registrant as specified in its charter)
England and Wales
(Jurisdiction of incorporation or organization)
1-3 Strand, London WC2N 5EH, England
(Address of principal executive offices)
Justine Campbell
011 44 20 7004 3000
Facsimile No. 011 44 20 7004 3004
Group General Counsel and Company Secretary
National Grid plc
1-3 Strand London WC2N 5EH, England
(Name, Telephone, E-mail and/or Facsimile number and Address of Company Contact Person)

Securities registered or to be registered pursuant to Section 12(b) of the Securities Exchange Act of 1934:

Title of each classTrading Symbol(s)Name of each exchange on which registered
Ordinary Shares of 12 204/473 pence eachNG
The New York Stock Exchange*
American Depositary Shares, each representing fiveNGGThe New York Stock Exchange
5.602% Notes due 2028 NGG28The New York Stock Exchange
5.809% Notes due 2033NGG33The New York Stock Exchange
5.418% Notes due 2034NGG34The 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: None.

Securities for which there is a reporting obligation pursuant to Section15(d) of the Securities Exchange Act of 1934: None.




The number of outstanding shares of each of the issuer’s classes of capital or common stock as of 31 March 2024 was
Ordinary Shares of 12 204/473 pence each    3,967,138,214

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act: Yes R No £

If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. Yes £ No R

Note — Checking the box above will not relieve any registrant required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 from their obligations under those Sections.

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days: Yes R No £

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).: Yes R No £

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or an emerging growth company. See definition of “large accelerated filer” “accelerated filer” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer R
Non-accelerated filer £
 Accelerated filer £
Emerging growth company £

If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standardsprovided pursuant to Section 13(a) of the Exchange Act.  ☐

†The term “new or revised financial accounting standard” refers to any update issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, 2012.

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. R

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing:

U.S. GAAP £
International Financial Reporting Standards as issued by the International Accounting Standards Board R
Other £

If “Other” has been checked in response to the previous question, indicate by check mark which financial statement item the registrant has elected to follow. Item 17 £ Item 18 £

If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes £ No R

This constitutes the annual report on Form 20-F of National Grid plc (the “Company”) in accordance with the requirements of the US Securities and Exchange Commission (the “SEC”) for the year ended 31 March 2024 and is dated 23 May 2024. Details of events occurring subsequent to the approval of the annual report on 22 May 2024 are summarised in section “Further Information” which forms a part of this Form 20-F. The content of the Group’s website (www.nationalgrid.com/uk) should not be considered to form part of this annual report on Form 20-F.







Form 20-F Cross Reference Table

ItemForm 20-F captionLocation in the documentPage(s)
1Identity of directors, senior management and advisorsNot applicable
2Offer statistics and expected timetableNot applicable
3Key Information
3A [Reserved]
3B Capitalization and indebtednessNot applicable
3C Reasons for the offer and use of proceedsNot applicable
3D Risk Factors
“Additional Information—Internal control and risk factors—Risk factors”
226-231
4Information on the company
4A History and development of the company“Strategic Report—National Grid at a glance”; “—Where we operate”; “—Our business model: “What we do” “—How we create value”2-5
“Strategic Report—Chair’s statement”6
“Strategic Report—Chief Executive’s review” 7-9
“Strategic Report—Our business environment”12-15
“Strategic Report—Succeeding with our strategy”16-17
“Strategic Report—Our key performance indicators (KPI)”18-21
“Strategic Report—Our business units “—UK Electricity Transmission (UK ET)”; “—UK Electricity System Operator (ESO)”; “—UK Electricity Distribution (UK ED)”; —New England”; —New York”; “—National Grid Ventures (NGV)”; “—Other activities”32-36
“Strategic Report—Financial review—Summary of Group financial performance for the year ended 31 March 2024”61-73
“Financial Statements—Notes to the consolidated financial statements—2. Segmental analysis—(c) Capital investment”139
“Financial Statements—Notes to the consolidated financial statements—10. Assets held for sale and discontinued operations”156-158
“Additional Information—The business in detail—UK Regulation”; “—US Regulation” and “—Summary of US price controls and rate plans”220-225
“Additional Information—Shareholder information—Articles of Association—General”232
“Additional Information—Shareholder Information— Documents on display” 233
“Additional Information—Other unaudited financial information—Alternative performance measures/non-IFRS reconciliations—Capital investment at constant currency” 248
“Additional Information—Want more information or help?”263
4B Business overview“Strategic Report—National Grid at a glance”; “—Where we operate”; “—Our business model: “What we do” “—How we create value”2-5
“Strategic Report—Chair’s statement”6
“Strategic Report—Our Business environment”12-15
“Strategic Report—Succeeding with our strategy”16-17
i



“Strategic Report—Our business units “—UK Electricity Transmission (UK ET)”; “—UK Electricity System Operator (ESO)”; “—UK Electricity Distribution (UK ED)”; —New England”; —New York”; “—National Grid Ventures (NGV)”; “—Other activities”32-36
“Strategic Report—Financial review—Segmental operating profit”63-66
“Financial Statements—Notes to the consolidated financial statements—2. Segmental analysis”137-139
“Financial Statements—Notes to the consolidated financial statements—3. Revenue”140-143