@MattC899781 wrote
Looking at my information on ssa.gov, I see they are withholding 10% of the balance after the medicare premium is subtracted. Elsewhere I read that these premiums are only tax-deductible if I itemize, and then only beyond the 7.5% level.
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I don’t think your 1st sentence is right - if you elected the % that you want them to withhold, it is based on the whole SS payment before any (Part B) deductions (including any IRMMA) or anything else that is deducted since many people may have their MA premiums or PDP premiums also deducted.
The 1099 - SSA does give you a total synopsis of the total benefit paid, total Part B premiums (with any IRMMA), other premiums that are deductible and any taxes you have authorized to be deducted.
If you have other income in retirement, the tax on Social Security benefits might be what gets you on your taxes but these aren’t actually income tax since they go back into the SS Trust Fund to help preserve the program.
SSA.gov - Taxes on One’s SS benefit
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