3M : Prospectus filed pursuant to Rule 424(b)(5)

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Filed Pursuant to Rule 424(b)(5)

File No. 333-216219

The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement is not an offer to sell these securities and we are not soliciting an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

Subject to Completion, dated August 19, 2019

PRELIMINARY PROSPECTUS SUPPLEMENT (To prospectus dated February 24, 2017)

$

	3M Company
$	% Notes due 2023
$	% Notes due 2025
$	% Notes due 2029
$	% Notes due 2049

We are offering $ aggregate principal amount of % Notes due 2023 (the " 2023 notes "), $ aggregate principal amount of % Notes due

2025 (the " 2025 notes "), $ aggregate principal amount of % Notes due 2029 (the " 2029 notes ") and $ aggregate principal amount of %

Notes due 2049 (the " 2049 notes " and, together with the 2023 notes, the 2025 notes and the 2029 notes, the " notes "). We will pay interest on the notes on and of each year, beginning on , 2020. The 2023 notes will mature on , 2023, the 2025 notes will mature on , 2025, the 2029 notes will mature on , 2029 and the 2049 notes will mature on , 2049.

We may redeem some or all of the notes at any time, and from time to time, at the applicable redemption prices described in this prospectus supplement. See

"Description of the Notes-Optional Redemption." In the event that we do not consummate the Acelity Acquisition (as defined herein) on or prior to May 1, 2020

or the Stock Purchase Agreement (as defined herein) is terminated at any time prior thereto, we will be required to redeem all of the outstanding notes of each

series on a special mandatory redemption date at a redemption price equal to 101% of the aggregate principal amount of the notes, plus accrued and unpaid interest,

if any, to, but excluding, the special mandatory redemption date. See "Description of the Notes-Special Mandatory Redemption."

The notes will be our unsecured and unsubordinated obligations and will rank equally with our existing and future unsecured and unsubordinated

indebtedness.

Investing in the notes involves risks. See " Risk Factors " on page S-5.

	Per 2023 Note	Per 2025 Note	Per 2029 Note	Per 2049 Note	Total
Public offering price	%	%	%	%	$
Underwriting discount	%	%	%	%	$
Proceeds, before expenses, to us	%	%	%	%	$

Interest on the notes will accrue from , 2019.

Neither the Securities and Exchange Commission (" SEC ") nor any other regulatory body has approved or disapproved of these securities or passed upon the accuracy and adequacy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

The notes will be ready for delivery in book-entry form only through the facilities of The Depository Trust Company (" DTC ") for the accounts of its participants, including Euroclear Bank SA/NV, as operator of the Euroclear System, and Clearstream Banking, S.A., on or about , 2019.

Joint Book-Running Managers

Goldman Sachs & Co. LLC	BofA Merrill Lynch	Morgan Stanley	Wells Fargo Securities
Barclays	Citigroup	Credit Suisse	Deutsche Bank Securities	J.P. Morgan
	The date of this prospectus supplement is	, 2019.

Table of Contents

TABLE OF CONTENTS
Prospectus Supplement
	Page
ABOUT THIS PROSPECTUS SUPPLEMENT	S-ii
SUMMARY	S-1
RISK FACTORS	S-5
USE OF PROCEEDS	S-6
DESCRIPTION OF THE NOTES	S-7
CERTAIN MATERIAL U.S. FEDERAL TAX CONSIDERATIONS	S-14
UNDERWRITING	S-19
LEGAL MATTERS	S-25
EXPERTS	S-26
WHERE YOU CAN FIND MORE INFORMATION AND INCORPORATION BY REFERENCE	S-27
Prospectus
ABOUT THIS PROSPECTUS	3
WHERE YOU CAN FIND ADDITIONAL INFORMATION	3
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE	3
THE COMPANY	4
RISK FACTORS	4
RATIOS OF EARNINGS TO FIXED CHARGES	4
USE OF PROCEEDS	4
DESCRIPTION OF THE SECURITIES WE MAY OFFER	4
DEBT SECURITIES	5
CAPITAL STOCK	15
PLAN OF DISTRIBUTION	18
LEGAL MATTERS	18
EXPERTS	18
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ABOUT THIS PROSPECTUS SUPPLEMENT

This document consists of two parts. The first part is the prospectus supplement, which describes the specific terms of this offering. The second part is the prospectus, which describes more general information, some of which may not apply to this offering. You should read this prospectus supplement, any related free writing prospectus that we provide to you and the accompanying prospectus, together with the additional information described under the heading "Where You Can Find More Information and Incorporation By Reference" elsewhere in this prospectus supplement. These documents contain information you should consider and rely on when making your investment decision. We have not, and the underwriters have not, authorized anyone else to provide you with different or additional information. If anyone provides you with different or inconsistent information, you should not rely on it.

This prospectus supplement and the accompanying prospectus do not constitute an offer to sell or a solicitation of an offer to buy any securities other than the

notes. This prospectus supplement and the accompanying prospectus do not constitute an offer to sell or a solicitation of an offer to buy such notes in any

circumstances in which such offer or solicitation is unlawful.

Information in this prospectus supplement, any related free writing prospectus that we provide to you and the accompanying prospectus may change after the

date on the front of the applicable document. You should not interpret the delivery of this prospectus supplement or the accompanying prospectus or the sale of the

notes as an indication that there has been no change in our affairs since those dates.

None of this prospectus supplement, the accompanying prospectus or any related free writing prospectus is a prospectus for the purposes of the Prospectus

Regulation (as defined below). This prospectus supplement, the accompanying prospectus and any related free writing prospectus have been prepared on the basis that any offer of notes in any Member State of the European Economic Area (the " EEA ") will only be made to a legal entity which is a qualified investor under the Prospectus Regulation (" Qualified Investors "). Accordingly any person making or intending to make an offer in that Member State of notes which are the subject of the offering contemplated in this prospectus supplement, the accompanying prospectus and any related free writing prospectus may only do so with respect to Qualified Investors. Neither 3M nor the underwriters have authorized, nor do they authorize, the making of any offer of notes other than to Qualified Investors. The expression " Prospectus Regulation " means Regulation (EU) 2017/1129.

PROHIBITION OF SALES TO EEA RETAIL INVESTORS -The notes are not intended to be offered, sold or otherwise made available to and should not be offered, sold or otherwise made available to any retail investor in the EEA. For these purposes, a " retail investor " means a person who is one (or more) of: (i) a retail client as defined in point (11) of Article 4(1) of Directive 2014/65/EU, as amended (" MiFID II "); or (ii) a customer within the meaning of Directive (EU) 2016/97 (the " Insurance Distribution Directive "), where that customer would not qualify as a professional client as defined in point (10) of Article 4(1) of MiFID II; or (iii) not a qualified investor as defined in the Prospectus Regulation. Consequently no key information document required by Regulation (EU) No 1286/2014, as amended (the " PRIIPs Regulation ") for offering or selling the notes or otherwise making them available to retail investors in the EEA has been prepared and therefore offering or selling the notes or otherwise making them available to any retail investor in the EEA may be unlawful under the PRIIPs Regulation.

The communication of this prospectus supplement, the accompanying prospectus, any related free writing prospectus and any other documents or materials

relating to the issue of the notes offered hereby is not being made, and such documents and/or materials have not been approved, by an authorized person for the purposes of section 21 of the United Kingdom's Financial Services and Markets Act 2000, as amended (the " FSMA "). Accordingly, such documents and/or materials are not

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being distributed to, and must not be passed on to, the general public in the United Kingdom. The communication of such documents and/or materials as a financial

promotion is only being made to those persons in the United Kingdom who have professional experience in matters relating to investments and who fall within the

definition of investment professionals (as defined in Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the " Financial Promotion Order ")) or who fall within Article 49(2)(a) to (d) of the Financial Promotion Order, or who are any other persons to whom it may otherwise lawfully be made under the Financial Promotion Order (all such persons together being referred to as " relevant persons "). In the United Kingdom, the notes offered hereby are only available to, and any investment or investment activity to which this prospectus supplement, the accompanying prospectus and any related free writing prospectus relates will be engaged in only with, relevant persons. Any person in the United Kingdom that is not a relevant person should not act or rely on this prospectus supplement, the accompanying prospectus or any related free writing prospectus or any of their contents.

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