Yes it needs to go back ... look at the outside of the envelope where the stamp would be ... see the box that says taxpayer deceased ? Check that box and return the check uncashed.
The IRS has requested that these checks be marked VOID in the signature area on the back and returned to the refund inquiry unit that serves your state. I am sorry for your loss.
Here is the list of addresses, based on the residence state of the deceased individual:
Maine, Maryland, Massachusetts, New Hampshire, Vermont
Andover Refund Inquiry Unit
1310 Lowell St.
Mail Stop 666A
Andover, MA 01810
Georgia, Iowa, Kansas, Kentucky, Virginia
Atlanta Refund Inquiry Unit
4800 Buford Hwy.
Mail Stop 112
Chamblee, GA 30341
Florida, Louisiana, Mississippi, Oklahoma, Texas
Austin Refund Inquiry Unit
3651 S Interregional Hwy. 35
Mail Stop 6542
Austin, TX 78741
New York
Brookhaven Refund Inquiry Unit
5000 Corporate Ct.
Mail Stop 547
Holtsville, NY 11742
Alaska, Arizona, California, Colorado, Hawaii, Nevada, New Mexico, Oregon, Utah, Washington, Wisconsin, Wyoming
Fresno Refund Inquiry Unit
5045 E Butler Ave.
Mail Stop B2007
Fresno, CA 93888
Arkansas, Connecticut, Delaware, Indiana, Michigan, Minnesota, Missouri, Montana, Nebraska, New Jersey, Ohio, West Virginia
Kansas City Refund Inquiry Unit
333 W Pershing Rd.
Mail Stop 6800, N-2
Kansas City, MO 64108
Alabama, North Carolina, North Dakota, South Carolina, South Dakota, Tennessee
Memphis Refund Inquiry Unit
5333 Getwell Rd.
Mail Stop 8422
Memphis, TN 38118
District of Columbia, Idaho, Illinois, Pennsylvania, Rhode Island
Philadelphia Refund Inquiry Unit
2970 Market St.
DP 3-L08-151
Philadelphia, PA 19104
A foreign country, U.S. possession or territory, or use an APO or FPO address, or file Form 2555 or 4563, or are a dual-status alien
Austin Refund Inquiry Unit
3651 S Interregional Hwy. 35
Mail Stop 6542 AUSC
Austin, TX 78741
Yes, if you are not the recipient of the stimulus check it should be returned per the instructions in the Q&A about repayments on the IRS.gov website. Go to www.irs.gov/coronavirus/economic-impact-payment-information-center under EIP Eligibility and General Information question # 10 to find the link to the instructions.