Bylaw Amendment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): December 10, 2025 W.W. Grainger, Inc. (Exact name of registrant as specified in its charter) Illinois 1-5684 36-1150280 (State or other jurisdiction of incorporation) (Commission file number) (I.R.S. Employer Identification No.) 100 Grainger Parkway 60045-5201 Lake Forest, Illinois (Zip Code) (Address of principal executive offices) Registrant’s telephone number, including area code: ( 847 ) 535-1000 Not Applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: ☐  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)   ☐  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)   ☐  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))   ☐  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act: Title of Each Class Trading Symbol Name of Each Exchange on Which Registered Common Stock GWW New York Stock Exchange Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).   Emerging growth company      ☐ If an emerging growth company, 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 standards provided pursuant to Section 13(a) of the Exchange Act. ☐          Item 5.03. Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year On December 10, 2025 (the “Effective Date”), the Board of Directors of W.W. Grainger, Inc. (the “Company”) approved amendments to the Company’s By-Laws (the “By-Laws”), effective as of the Effective Date. The amendments reflect updates to modernize and clarify certain provisions relating to virtual annual shareholder meetings and remote communications and update or remove outdated terminology. The foregoing summary of the amendment to the By-Laws does not purport to be complete and is qualified in its entirety by reference to the By-Laws, a copy of which is attached as Exhibit 3.1 to this Current Report on Form 8-K and is incorporated herein by reference. ______________________________________________________________________ Item 9.01. Financial Statements and Exhibits. (d) Exhibits. Exhibit No. Description 3.1 By- L aws of W.W. Grainger, Inc. , as Amended 104         Cover Page Interactive Data File (the cover page XBRL tags are embedded within the Inline XBRL Document) SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Date: December 11, 2025 W.W. GRAINGER, INC.  By: /s/ Paul Stanukinas  Name: Paul Stanukinas  Title: Vice President and Corporate Secretary