United States · IRS Publication 915
Taxable Social Security benefits.
Enter your net benefits, other income and tax-exempt interest to see how much of your Social Security is taxable on a federal return.
Up to 50% of benefits can be taxable once provisional income passes $25,000 (single) or $32,000 (married filing jointly), and up to 85% once it passes $34,000 or $44,000. No more than 85% is ever taxable.
Your inputs
Estimate
How the calculation works
Provisional income = other income (less adjustments) + tax-exempt interest + 50% of your net benefits. Compare it with your base amount: $25,000 single, head of household or qualifying surviving spouse; $32,000 married filing jointly; $25,000 married filing separately if you lived apart from your spouse all year; $0 if you lived with your spouse at any time.
Following Worksheet 1: take the excess over the base amount. The first $9,000 of excess ($12,000 joint) is taxed at 50%, capped at 50% of benefits; everything above that is taxed at 85%. Taxable benefits are the smaller of that sum and 85% of benefits. If you are married filing separately and lived with your spouse, the base amount is $0, so taxable benefits are the smaller of 85% of your provisional income and 85% of your benefits.
Worked example
Single, benefits $24,000, other income $30,000, tax-exempt interest $1,000. Provisional income = $12,000 + $30,000 + $1,000 = $43,000. Excess over $25,000 is $18,000: $9,000 at 50% = $4,500 (under the $12,000 cap), plus $9,000 at 85% = $7,650. Total $12,150, below the 85% cap of $20,400, so $12,150 (about 51%) of benefits is taxable.
Not modelled: savings-bond, adoption, foreign-earned-income and Puerto Rico/American Samoa exclusions, traditional IRA deductions with a workplace plan (Pub. 590-A worksheets), lump-sum elections, and state taxes. Many states do not tax Social Security at all; check yours separately.
Official sources: IRS Publication 915 and IRS Topic no. 423, both opened September 30, 2026. The base amounts are not indexed for inflation.
Frequently asked questions
Is Social Security taxable?
Sometimes. If your only income is Social Security, your benefits generally are not taxable. With other income, up to 50% or 85% of benefits can be taxable depending on provisional income.
Does tax-exempt interest count?
Yes. Tax-exempt interest, such as municipal bond interest, is added to provisional income even though the interest itself is not taxed.
Are the thresholds adjusted for inflation?
No. The $25,000, $32,000, $34,000 and $44,000 amounts are fixed in law, so more retirees cross them over time.
What does 85% taxable mean?
It means up to 85% of your benefits are added to taxable income and taxed at your regular rate. It does not mean you pay 85% of your benefits in tax.
Not tax advice
This is an educational estimate of one worksheet, not a tax return or personalized tax advice. Confirm your figures with the Form 1040 instructions or a qualified tax professional.