UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934
(Amendment No. _)*

Crestwood Equity Partners LP

(Name of Issuer)

Preferred Units representing limited partnership interest

(Title of Class of Securities)

226344307

(CUSIP Number)

December 31, 2020

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

     x Rule 13d-1(b)

     o Rule 13d-1(c)

     o Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 226344307

CUSIP No. 226344307

CUSIP No. 226344307 

CUSIP No. 226344307

SCHEDULE 13G

Crestwood Equity Partners LP (the “Issuer”)

811 Main Street, Suite 3400

Houston, TX 77002

This statement is filed on behalf of each of the following person (collectively, the “Reporting Persons”):

This statement relates to the Units (as defined herein) held for Magnetar Constellation IV LLC (“Constellation Fund”), Magnetar Energy Master Fund LLC (“Energy Master Fund”), MTP Emerald Fund LLC (“Emerald Fund”), Magnetar Andromeda Select Fund LLC (“Andromeda Select Fund), all Delaware limited liability companies; Magnetar Structured Credit fund LP (“Structured Credit Fund”) and MTP Energy Fund LP (“MTP Fund”), both Delaware limited partnerships; collectively (the “Magnetar Funds”). MTP Energy Management LLC (“MTP Energy”) serves as the investment adviser to the Energy Master Fund, MTP Fund and serves as the Manager to the Emerald Fund, and as such, MTP Energy exercises voting and investment power of the Units held for the aforementioned funds’ accounts. Magnetar Financial serves as the investment adviser to the Constellation Fund, Andromeda Select Fund and Structured Credit Fund, and as such, Magnetar Financial exercises voting and investment power over the Units held for the aforementioned funds’ accounts. Magnetar Financial is the sole member of MTP Energy and Magnetar Capital Partners serves as the sole member and parent holding company of Magnetar Financial. Supernova Management is the general partner of Magnetar Capital Partners. The manager of Supernova Management is Mr. Litowitz.

The address of the principal business office of each of Magnetar Financial, Magnetar Capital Partners, Supernova Management, and Mr. Litowitz is 1603 Orrington Avenue, 13^th Floor, Evanston, Illinois 60201.

226344307

(e) x An investment adviser in accordance with §240.13d–1(b)(1)(ii)(E)

(g) x A parent holding company or control person in accordance with §240.13d–1(b)(1)(ii)(G)

As of December 31, 2020, each of Magnetar Financial, Magnetar Capital Partners, Supernova Management and Mr. Litowitz held 4,553,641 Units. The amount consists of (A) 1,310,603 Units held for the account of Constellation Fund; (B) 546,699 Units held for the account of Energy Master Fund; (C) 1,569,708 Units held for the account of Structured Credit Fund; (D) 419,617 Units held for the account of Andromeda Select Fund; (E) 484,567 Units held for the account of MTP Fund; and (F) 222,447 Units held for the account of Emerald Fund. The Units held by the Magnetar Funds represent approximately 6.39% of the total number of Units outstanding (calculated pursuant to Rule 13d-3(d)(1)(i)) of the outstanding Units of the Issuer).

(i) As of December 31, 2020, each of Reporting Persons were deemed to be the beneficial owner constituting approximately 6.39% of the total number of Units outstanding (based upon the information provided by the Issuer in its Form 10-Q filed with the SEC on October 29, 2020, there were approximately 71,257,445 Units outstanding as of September 30, 2020).

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following ¨.

This Item 6 is not applicable.

This Item 7 is not applicable.

This Item 8 is not applicable.

This Item 9 is not applicable.

By signing below the Reporting Persons certifies that, to the best of their knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

EXHIBIT INDEX

EXHIBIT A

JOINT FILING AGREEMENT

The undersigned hereby agree that the statement on Schedule 13G with respect to the Units of Crestwood Equity Partners LP dated as of December 31, 2020 is, and any amendments thereto (including amendments on Schedule 13D) signed by each of the undersigned shall be, filed on behalf of each of us pursuant to and in accordance with the previsions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended.