NGG Form 6-K: Exhibit 99.1 Half Year Results announcement filed

Rhea-AI Filing Summary

National Grid plc furnished a Form 6-K announcing that its accompanying Exhibit 99.1—an announcement sent to the London Stock Exchange titled “National Grid 2025/26 Half Year Results Statement”—has been provided.

The report and Exhibit 99.1 are incorporated by reference into the company’s registration statements on Form F-3 and Form S-8, becoming part of those filings from the date of submission, to the extent not superseded by later filings. The company notes the filing date as 6 November 2025.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

UNDER THE SECURITIES EXCHANGE ACT OF 1934

For the month of November 2025

Commission File Number: 001-14958

NATIONAL GRID plc

(Translation of Registrant’s Name into English)

1-3 Strand

London WC2N 5EH, England

(Address of principal Executive Office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.
☒  Form 20-F      ☐  Form 40-F

INCORPORATION BY REFERENCE

This report and Exhibit 99.1 of this report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form F-3 (Registration Numbers 333-281812 and 333-256888) and Form S-8 (Registration Numbers 333-184558, 333-170716, 333-175852, 333-155527, 333-149828, 333-107727, 333-103768, 333-97249, 333-65968, and 333-33094) of National Grid plc (the "Company") (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

Please see Exhibit 99.1 Announcement sent to the London Stock Exchange on 6 November 2025 — 'National Grid 2025/26 Half Year Results Statement'

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

						NATIONAL GRID plc
						By:			/s/Julian Baddeley _______________________
									Julian Baddeley Company Secretary

Date: 6 November 2025

EXHIBIT INDEX

Exhibit No.			Description
99.1			Exhibit 99.1 Announcement sent to the London Stock Exchange on 6 November 2025 — 'National Grid 2025/26 Half Year Results Statement'

FAQ

What did National Grid (NGG) file?

National Grid filed a Form 6-K furnishing Exhibit 99.1, an announcement sent to the London Stock Exchange titled “National Grid 2025/26 Half Year Results Statement.”

What is included in Exhibit 99.1 for NGG?

Exhibit 99.1 is the announcement sent to the London Stock Exchange on 6 November 2025 regarding the 2025/26 Half Year Results Statement.

How does this 6-K affect National Grid’s registration statements?

The report and Exhibit 99.1 are incorporated by reference into National Grid’s Form F-3 and Form S-8 registration statements, becoming part of those filings from the submission date.

Which registration forms are referenced for NGG?

Form F-3 and Form S-8 registration statements are referenced for incorporation by reference.

When was the announcement sent to the LSE?

The announcement was sent to the London Stock Exchange on 6 November 2025.

Does this filing include financial results for NGG?

The document points to financial results in Exhibit 99.1; specific figures are not included in the provided text.