Unfortunately you cannot legally deposit an IRS refund check which is made payable to both you and your spouse. There are various reasons for this, but one of the main problems the IRS has had in the past is with taxpayers who are separated or divorced, and where one taxpayer is trying to keep the entire refund without their spouse's knowledge. When something like that occurs, the other spouse may come back and file a claim for their share of the refund. The IRS can hold a bank responsible in such an instance where they accept a check with only one endorsement.
Your only option here would be to return the check to the IRS and request that it be re-issued in your name only. In the case where a spouse is "missing", you would also need to provide one of the following documents:
1. Copy of police report or missing person report filed with police.
2. Certification from state or local government that the spouse cannot be found.
3. A copy of notice printed in a newspaper where you have tried to locate the spouse.
I am giving you a link below to a section of the IRS website which addresses these issues. Please refer to the section for joint filers requesting a refund in one name.
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