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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1. Name and Address of Reporting Person *   BILLHORN JILL M. 2. Date of Event Requiring Statement (Month/Day/Year) 01/01/2019 3. Issuer Name and Ticker or Trading Symbol CDW Corp [CDW] (Last) (First) (Middle) C/O CDW CORPORATION, 200 N MILWAUKEE AVE 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) See Remarks 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) VERNON HILLS, IL 60061 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, par value $0.01 13,788 D Â

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 Option (Right to Buy)	  (1)	02/27/2028	Common Stock, par value $0.01	6,872	$ 73.49	D	Â
Employee Stock Option (Right to Buy)	  (2)	02/28/2027	Common Stock, par value $0.01	5,456	$ 58.9	D	Â
Employee Stock Option (Right to Buy)	  (3)	03/02/2026	Common Stock, par value $0.01	2,451	$ 39.79	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
BILLHORN JILL M. C/O CDW CORPORATION 200 N MILWAUKEE AVE VERNON HILLS, IL 60061	Â	Â	  See Remarks	Â

Signatures

/s/ Robert J. Welyki, Attorney-in-Fact		01/08/2019
**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)	6,872 options were granted of which one third of the shares vest on each of February 27, 2019, 2020 and 2021. The grant was made under the CDW Corporation 2013 Long-Term Incentive Plan.
(2)	8,183 options were granted of which one third of the shares vest on each of February 28, 2018, 2019 and 2020. The grant was made under the CDW Corporation 2013 Long-Term Incentive Plan.
(3)	7,351 options were granted of which one third of the shares vest on each of March 02, 2017, 2018 and 2019. The grant was made under the CDW Corporation 2013 Long-Term Incentive Plan.
  Remarks: Senior Vice President- Corporate Sales

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