UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.    )

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☐	Preliminary Proxy Statement
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☐	Definitive Proxy Statement
☒	Definitive Additional Materials
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ZIX CORPORATION
(Name of registrant as specified in its charter)
(Name of person(s) filing proxy statement, if other than the registrant)
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*** Exercise Your Right to Vote ***

Important Notice Regarding the Availability of Proxy Materials for the

Shareholder Meeting to Be Held on June 06, 2018

		Meeting Information
		Meeting Type:	Annual Meeting
	ZIX CORPORATION	For holders as of:	April 13, 2018
		Date:    June 06, 2018	Time: 10:00 AM CDT
		Location:   Cityplace Conference Center
		Turtle Creek I Room
		2711 North Haskell Avenue   Dallas, Texas 75204

ZIX CORPORATION   2711 N. HASKELL AVENUE   SUITE 2200, LB36   DALLAS, TX 75204-2960	You are receiving this communication because you hold shares in the above named company.
	This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side).
	We encourage you to access and review all of the important information contained in the proxy materials before voting.
	See the reverse side of this notice to obtain proxy materials and voting instructions.

Before You Vote  

How to Access the Proxy Materials

Proxy Materials Available to VIEW or RECEIVE:

1. Notice & Proxy Statement        2. Annual Report        

How to View Online:

Have the information that is printed in the box marked by the arrow     (located on the following page) and visit: www.proxyvote.com.

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How To Vote  

Please Choose One of the Following Voting Methods

    Vote In Person: Many shareholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares.   Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box marked by the arrow     available and follow the instructions.   Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card.  

	Voting items
	The Board of Directors recommends you vote FOR the following: 1.     Election of Directors
	Nominees
	01     Mark J. Bonney         02 Taher A. Elgamal         03 Robert C. Hausmann        04 Maribess L. Miller        05 Richard D. Spurr
	06     David J. Wagner
	The Board of Directors recommends you vote FOR proposals 2, 3 and 4.
	2   Ratification of Appointment of Whitley Penn LLP as Independent Registered Public Accountants.
	3   Advisory vote to approve executive compensation.
	4   Approve the 2018 Omnibus Incentive Plan.
	NOTE: Any other business properly brought before the meeting or any adjournment or postponement thereof.