UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 14A

(Rule 14a -101)

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Ryerson Holding Corporation

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(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 Stockholder Meeting to Be Held on April 24, 2019 Meeting Information Meeting Type: Annual Meeting For holders as of: March 01, 2019 RYERSON HOLDING CORPORATION Date: April 24, 2019 Time: 2:00 PM CDT Location:  JW Marriott Houston Downtown 806 Main Street Houston, TX 77002 BARCODE 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. RYERSON RYERSON HOLDING CORPORATION 227 W. MONROE ST., 27th FLOOR CHICAGO, IL 60606 Investor Address Line 1 Investor Address Line 2 Investor Address Line 3 Investor Address Line 4 Investor Address Line 5 John Sample 1234 ANYWHERE STREET ANY CITY, ON A1A 1A1 1 OF 2 12 15 Broadridge Internal Use Only Job # Envelope # Sequence # # of # Sequence # 0000400431_1 R1.0.1.18

Before You Vote How to Access the Proxy Materials Proxy Materials Available to VIEW or RECEIVE: I. Notice & Proxy Statement 2. IOK Warp How to View Online: Have the information that is printed in the box marked by the arrow XXXX XXXX XXXX XXXX (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 XXXX XXXX XXXX XXXX (located on the following page) in the subject line. 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 10, 2019 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 XXXX XXXX XXXX XXXX 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. Internal Use Only 0000400431_2 R1.0.1.18

Voting items The Board of Directors recommends you vote FOR the following: 1. Election of Directors Nominees 01 Stephen P. Larson 02 Philip E. Norment The Board of Directors recommends you vote FOR proposals 2. and 3. 2. Ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for 2019. 3. Approval of the Amended and Restated 2014 Omnibus Incentive Plan. NOTE: Such other business as may properly come before the Annual Meeting BARCODE 0000 0000 0000 0000 Broadridge Internal Use Only xxxxxxxxxx xxxxxxxxxx Cusip Job # Envelope # Sequence # # of # Sequence # 0000400431_3 R1.0.1.18

Reserved for Broadridge Internal Control Information NAME THE COMPANY NAME INC. - COMMON 123,456,789,012.12345 THE COMPANY NAME INC. - CLASS A 123,456,789,012.12345 THE COMPANY NAME INC. - CLASS B 123,456,789,012.12345 THE COMPANY NAME INC. - CLASS C 123,456,789,012.12345 THE COMPANY NAME INC. - CLASS D 123,456,789,012.12345 THE COMPANY NAME INC. - CLASS E 123,456,789,012.12345 THE COMPANY NAME INC. - CLASS F 123,456,789,012.12345 THE COMPANY NAME INC. - 401 K 123,456,789,012.12345 THIS SPACE RESERVED FOR SIGNATURES IF APPLICABLE Broadridge Internal Use Only Job # Envelope # Sequence # # of # Sequence # 0000400431_4 R1.0.1.18