Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  WESTPHAL MARK W
 2. Date of Event Requiring Statement (Month/Day/Year)
01/31/2018		 3. Issuer Name and Ticker or Trading Symbol
Post Holdings, Inc. [POST]
(Last)
(First)
(Middle)
C/O POST HOLDINGS, INC., 2503 S. HANLEY ROAD		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
PRES., MICHAEL FOODS
 5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

ST. LOUIS, MO 63144		 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 31,788 (1)
D
 
Common Stock 6,440.518
I
By 401(k) Plan

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Options (right to buy)   (2) 12/01/2027 Common Stock 20,508 $ 79.52 D  

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
WESTPHAL MARK W
C/O POST HOLDINGS, INC.
2503 S. HANLEY ROAD
ST. LOUIS, MO 63144		       PRES., MICHAEL FOODS  

Signatures

/s/ Diedre J. Gray, Attorney-in-Fact 02/09/2018
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Includes 21,021 unvested restricted stock units. Each restricted stock unit represents a contingent right to receive one share of Post Holdings, Inc. common stock upon vesting.
(2) The option to purchase 20,508 shares of common stock was awarded on December 1, 2017 under the Post Holdings, Inc. 2016 Long-Term Incentive Plan in a transaction exempt under Rule 16b-3 and vest in equal increments over three years from the date of grant.
 
Remarks:
See attached Exhibit 24 - Power of Attorney.

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