GWW WW Grainger Inc

Free Writing Prospectus

Filed pursuant to Rule 433

Supplementing the Preliminary

Prospectus Supplement dated February 21, 2020

and the Prospectus dated February 20, 2020

Registration No. 333-236530

*Note: An explanation of the significance of ratings may be obtained from the ratings agencies. Generally, ratings agencies base their ratings on such material and information, and such of their own investigations, studies and assumptions, as they deem appropriate. The security ratings above are not a recommendation to buy, sell or hold the securities offered hereby. The ratings may be subject to review, revision, suspension, reduction or withdrawal at any time by the rating agencies. Each of the security ratings above should be evaluated independently of any other security rating.

Under Rule 15c6-1 of the Securities Exchange Act of 1934, as amended, trades in the secondary market generally are required to settle in two business days, unless the parties to any such trade expressly agree otherwise.  Accordingly, purchasers who wish to trade the notes prior to two business days before the date of delivery will be required, by virtue of the fact that the notes initially settle in T+3, to specify an alternate settlement arrangement at the time of any such trade to prevent a failed settlement.  Purchasers of the notes who wish to trade the notes prior to two business days before the date of delivery should consult their advisors.

The issuer has filed a registration statement (including a prospectus) with the Securities and Exchange Commission (“SEC”) for the offering to which this communication relates.  Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer and this offering.  You may get these documents for free by visiting EDGAR on the SEC web site at www.sec.gov.  Alternatively, the issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus and supplement(s) thereto, if you request it by calling BofA Securities, Inc. toll-free at 1-800-294-1322 and J.P. Morgan Securities LLC collect at 1-212-834-4533.

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