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 Date: 6 June 2023 Commission File Number: 001-14958 NATIONAL GRID plc (Translation of registrant’s name into English) England and Wales (Jurisdiction of Incorporation) 1-3 Strand, London, WC2N 5EH, United Kingdom (Address of principal executive office) Indicate by check mark whether the registrant files or will file annua ...