UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

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

Exchange Act of 1934 (Amendment No.    )

Filed by the Registrant þ

Filed by a Party other than the Registrant ¨

Check the appropriate box:

¨ Preliminary Proxy Statement

¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

¨ Definitive Proxy Statement

þ Definitive Additional Materials

¨ Soliciting Material Pursuant to §240.14a-12

Cray Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

þ No fee required.

¨ Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

(1) Title of each class of securities to which transaction applies:

(2) Aggregate number of securities to which transaction applies:

(3) Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):

(4) Proposed maximum aggregate value of transaction:

(5) Total fee paid:

¨ Fee paid previously with preliminary materials.

¨ Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

(1) Amount Previously Paid:

(2) Form, Schedule or Registration Statement No.:

(3) Filing Party:

(4) Date Filed:

*** Exercise Your Right to Vote ***

Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting to Be Held on June 12, 2014.

CRAY INC.

CRAY INC.

901 FIFTH AVENUE, STE.1000

SEATTLE, WA 98164

ATTN: CAROL LYNN COLE

Meeting Information

Meeting Type: Annual Meeting

For holders as of: April 10, 2014

Date: June 12, 2014 Time: 3:00 p.m., PDT

Location: 901 Fifth Avenue

Fifth Avenue Conference Room

Seattle, WA 98164

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.

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

How to View Online:

Have the information that is printed in the box marked by the arrow 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 would like 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 (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 May 30, 2014 to facilitate timely delivery.

— How To Vote —

Please Choose One of the Following Voting Methods

Vote In Person: Many shareholder meetings have attendance requirements. 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. For a map and/or directions to our corporate headquarters, see our website, www.cray.com, under “About Cray — Contact Us.”

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 (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.

Voting Items

The Board of Directors recommends that you vote FOR the following nominees:

1. Election of Directors, each to serve a one-year term.

Nominees:

01) Prithviraj Banerjee

05) Daniel C. Regis

02) Stephen C. Kiely

06) Stephen C. Richards

03) Frank L. Lederman

07) Peter J. Ungaro

04) Sally G. Narodick

The Board of Directors recommends that you vote FOR the following proposals:

2. To ratify the appointment of Peterson Sullivan LLP as our independent registered public accounting firm for the year ending December 31, 2014.

3. To vote, on an advisory or non-binding basis, to approve the compensation of our Named Executive Officers.

NOTE: Such other business as may properly come before the Annual Meeting or any adjournment or postponement thereof.