If you lost your refund check, you should initiate a refund trace:

• Use Where's My Refund, call us at 800-829-1954 and use the automated system, or speak with a representative by calling 800-829-1040 (see telephone assistance for hours of operation).
• However, if you filed a married filing jointly return, you can’t initiate a trace using the automated systems. Call and speak with a representative to get the process started or download and complete Form 3911, Taxpayer Statement Regarding Refund PDF.

Your claim for a missing refund is processed one of two ways:

• If the check wasn't cashed, you'll receive a replacement check once the original check is canceled.
• If the refund check was cashed, the Bureau of the Fiscal Service (BFS) will provide you with a claim package that includes a copy of the cashed check. Follow the instructions for completing the claim package. BFS will review your claim and the signature on the canceled check before determining whether they can issue you a replacement check. The BFS review can take up to six weeks to complete.