SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

(Amendment No.     )

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☐	Soliciting Material Pursuant to § 240.14a-11(c) or § 240.14a-12

CLEARWATER PAPER CORPORATION

(Name of Registrant as Specified In Its Charter)

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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to Be Held on May 14, 2018. Meeting Information CLEARWATER PAPER CORPORATION Meeting Type: Annual Meeting For holders as of: March 19, 2018 Date: May 14, 2018 Time: 9:00 AM PDT Location: Grand Hyatt 721 Pine Street Seattle, WA 98101 You are receiving this communication because you hold shares in the company named above.  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. E42053-P01337-Z71662 CLEARWATER PAPER CORPORATION 601 W. RIVERSIDE AVENUE SUITE 1100 SPOKANE, WA 99201 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: NOTICE AND PROXY STATEMENT ANNUAL REPORT WITH FORM 10-K 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. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET: www.proxyvote.com 2) BY TELEPHONE: 1-800-579-1639 3) BY E-MAIL*: sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked by the arrow (located on the following page) in the subject line. . XXXX XXXX XXXX XXXX E42054-P01337-Z71662 . XXXX XXXX XXXX XXXX Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before April 30, 2018 to facilitate timely delivery. How To Vote Please Choose One of the Following Voting Methods Vote In Person: Many stockholder 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 (located on the following page) 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. . XXXX XXXX XXXX XXXX

Voting Items The Board of Directors recommends you vote FOR the following: Proposal 1 - Election of Directors Nominees: 1a. Linda K. Massman 1b. Alexander Toeldte The Board of Directors recommends a vote FOR Proposal 2. Proposal 2 - Ratification of the appointment of KPMG LLP as the Company's independent registered public accounting firm for 2018. The Board of Directors recommends a vote FOR Proposal 3. E42055-P01337-Z71662 Proposal 3 - Advisory vote to approve named executive officer compensation.

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