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): September 25, 2025

CLEAN HARBORS, INC.

(Exact name of registrant as specified in its charter)

Massachusetts	001-34223	04-2997780
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

42 Longwater Drive	Norwell	MA	02061-9149
(Address of Principal Executive Offices)			(Zip Code)

 Registrant’s telephone number, including area code (781) 792-5000

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))

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. ☐

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, $0.01 par value	CLH	New York Stock Exchange

Item 8.01.    Other Events.

On September 25, 2025, Clean Harbors, Inc. (the “Company”) issued a press release announcing that it had commenced a private offering of senior notes due 2033 to persons reasonably believed to be “qualified institutional buyers” in the United States, as defined in Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”), and to certain non-U.S. persons outside the United States in offshore transactions pursuant to Regulation S under the Securities Act.

On September 25, 2025, the Company issued a press release announcing the pricing of its previously announced offering of 5.750% senior notes due 2033 (the “Notes”).

Copies of the press releases are attached as Exhibit 99.1 and 99.2 to this Current Report on Form 8-K and are incorporated by reference into this Item 8.01.

Neither this Current Report on Form 8-K nor the press releases constitute an offer to sell, or the solicitation of an offer to buy, the Notes.

Item 9.01.    Financial Statements and Exhibits.

(d) Exhibits

Exhibit Number	Description
99.1	Press release of the Company relating to the announcement of the offering, dated September 25, 2025
99.2	Press release of the Company relating to the pricing of the offering, dated September 25, 2025
104	Cover Page Interactive Data File (embedded within the Inline XBRL document)

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SIGNATURES

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

	Clean Harbors, Inc.
	(Registrant)
September 25, 2025	/s/ Eric J. Dugas
	Executive Vice President and Chief Financial Officer

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