IRS Publication 554 — Tax Guide for Seniors
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This discussion explains the federal income tax rules for social security benefits and equivalent tier 1 railroad retirement benefits. Social security benefits include monthly retirement, survivor, and disability benefits. They don’t include supplemental security income (SSI) payments, which aren’t taxable. Equivalent tier 1 railroad retirement benefits are the part of tier 1 benefits that a railroad employee or beneficiary would have been entitled to receive under the social security system. They are commonly called the social security equivalent benefit (SSEB) portion of tier 1 benefits. If you received these benefits during 2025, you should have received a Form SSA -1099 or Form RRB -1099 (Form SSA-1042S or Form RRB -1042S if you are a nonresident alien) showing the amount of the benefits.
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