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): August 15, 2017

Trinseo S.A.

(Exact name of registrant as specified in its charter)

001-36473

(Commission

File Number)

(610) 240-3200

(Registrant’s telephone number, including area code)

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 (see General Instruction A.2. below):

o                                    Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o                                    Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o                                    Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o                                    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 o

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. o

Item 7.01 Regulation FD Disclosure.

Beginning on August 15, 2017, Trinseo Materials Operating S.C.A. and Trinseo Materials Finance, Inc., both wholly-owned indirect subsidiaries of Trinseo S.A. (collectively, the “Issuers”), intend to make available to potential investors certain information regarding the business of Trinseo S.A. in connection with a proposed debt refinancing transaction. Certain portions of that information are furnished hereto as Exhibit 99.1 and are incorporated herein by reference.

The completion of the proposed refinancing transaction is subject to market and other conditions and there can be no assurance to the terms of the proposed refinancing will occur.

This current report on Form 8-K contains “forward-looking statements” within the meaning of the federal securities laws, which involve risks and uncertainties. You can identify forward-looking statements because they contain words such as “believes,” “expects,” “may,” “will,” “should,” “seeks,” “approximately,” “intends,” “plans,” “estimates,” or “anticipates” or similar expressions that concern our strategy, plans or intentions. These forward-looking statements involve a number of risks, uncertainties, and other factors including the failure to consummate the notes offering or the new senior secured credit facility and potential changes in market conditions that could cause actual results to differ materially from those expressed or implied by such statement. We caution investors not to place undue reliance on these forward-looking statements. You are encouraged to read our filings with the SEC, available at www.sec.gov, for a discussion of these and other risks and uncertainties that we face.

The information contained in this Item 7.01 shall not be deemed filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to liability of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

Item 8.01 Other Events

On August 15, 2017, the Issuers entered into a purchase agreement with the representatives of certain initial purchasers, relating to the issuance and sale of $500 million in gross proceeds of the Issuers’ senior notes due 2025.

On August 15, 2017, Trinseo issued a press release announcing the pricing of the notes offering. A copy of the press release is attached as Exhibit 99.2 to this Current Report on Form 8-K and incorporated herein by reference.

Item 9.01 Financial Statements and Exhibits

(d) Exhibits.

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SIGNATURE

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

Date: August 15, 2017

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EXHIBIT INDEX

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