I received notice from SSA for an overpayment in 2021, requiring me to send them a large check…
my question, is if I paid taxes on SS payments I received in 2021 and then paid them back, do I need to amend my 2021 tax return?
No, the return for the year the Social Security payments were received should not be amended. IRS Publication 915 states: Repayment of benefits. Any repayment of benefits you made during 2021 must be subtracted from the gross benefits you received in 2021. It doesn’t matter whether the repayment was for a benefit you received in 2021 or in an earlier year.
The 2022 Form SSA-1099, Box 4 amount will report repayments made during 2022. This will offset the Box 3 amount of benefits paid in 2022. If the repayment exceeds the 2022 benefits received, the Net Benefits amount in Box 5 will be negative. In this situation refer to the IRS Publication 915, section entitled Repayments More Than Gross Benefits for the details about how that's handled.
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