Is my Social Security taxable?

How much of my Social Security is taxable?

None, up to 50%, or up to 85% of your benefits, never more than 85%. It depends on your income plus half your benefits, compared with $25,000 (single) or $32,000 (married filing jointly) for the 50% range and $34,000 or $44,000 for the 85% range.

Are the thresholds adjusted for inflation?

No. The IRS publication lists the same dollar amounts every year ($25,000 and $32,000, then $34,000 and $44,000) because they are fixed in the tax law, not indexed. As wages and cost-of-living increases grow, more retirees cross them each year.

Does 85% taxable mean I pay 85% tax?

No. It means 85% of your benefits are added to your taxable income and taxed at your normal bracket rates. At a 12% bracket, 85% taxable is roughly 10% of the benefit in tax.

What counts as income here?

Wages, pensions, IRA and 401(k) withdrawals, interest, dividends, capital gains and taxable Social Security together, plus tax-exempt interest (such as municipal bond interest), plus half of your Social Security benefits. Roth IRA withdrawals that are tax-free do not count.

What if I am married but file separately?

If you lived with your spouse at any time during the year, your base amount is $0 and up to 85% of benefits can be taxable from the first dollar. If you lived apart all year, the single thresholds apply.

Which number is on my SSA-1099?

Box 5 shows the net benefits paid for the year. That is the figure to enter here, before any Medicare premium or tax withholding is subtracted from the payment. Box 3 and box 4 show the parts that make it up.

Can I lower the taxable part?

Anything that lowers your other income lowers the taxable part: a qualified charitable distribution from an IRA, withdrawals from a Roth account instead of a traditional one, or the timing of capital gains. Because of the 50% and 85% ranges, an extra dollar of IRA income can add up to $1.85 of taxable income in the ranges where the benefit tax applies.

What the number means

The tax law does not tax Social Security the way it taxes wages. It first measures your “combined income”: your other income, plus tax-exempt interest, plus half of your benefits. Only when that figure is above a base amount do benefits start to enter taxable income, and never more than 85% of them. This calculator follows Worksheet 1 in IRS Publication 915 line by line, so the answer matches the Social Security Benefits Worksheet in the Form 1040 instructions.

How the worksheet works

Take half of your benefits and add your other income and tax-exempt interest, then subtract the adjustments to income from Schedule 1 that Publication 915 lists. If the result is not above the base amount ($25,000 single, $32,000 joint), nothing is taxable. Between the base amount and the adjusted base amount ($34,000 or $44,000, so a band of $9,000 or $12,000), 50% of each extra dollar is taxable, capped at half your benefits. Above that band, 85% of each extra dollar is added to the amount from the 50% range. The total can never be more than 85% of your benefits. For married people filing separately who lived together, the worksheet skips the middle step: 85% of the combined figure is taxable, capped at 85% of benefits.

Worked example: single, $24,000 in benefits

Say you receive $24,000 in benefits and have $30,000 of other income and $1,000 of tax-exempt interest. Half of the benefits is $12,000, so the combined figure is $43,000. That is $18,000 over the $25,000 base amount: the first $9,000 of it is taxed at 50% ($4,500) and the remaining $9,000 at 85% ($7,650). The sum, $12,150, is under the 85% cap of $20,400, so $12,150 of the benefits, or 50.6%, is taxable. For a married couple filing jointly with $36,000 of benefits and $40,000 of other income the combined figure is $58,000 and the taxable amount is $17,900 (49.7%). A single filer with $20,000 of benefits and $15,000 of other income has $25,000, which is $0 over the base amount, so $0 is taxable. With a large other income of $100,000, the cap binds: $20,400 of $24,000 (85%).

Common mistakes

One mistake is using adjusted gross income instead of the worksheet figure: the worksheet adds tax-exempt interest and half the benefits, so a retiree with no taxable income apart from municipal bond interest can still owe tax on benefits. Another is treating the thresholds as if they rose with inflation; the amounts in the worksheet are the same every year. A third is forgetting the separate-filing rule: a married couple who file separately and lived together get a base amount of $0, so with $20,000 of benefits and $10,000 of other income, $17,000 is taxable (85% of $20,000). Last, box 5 of the SSA-1099 is the net payment for the year, and a lump-sum payment covering earlier years can be treated under a special election in Publication 915, which this calculator does not model.

Limits of this calculator

It shows the taxable amount and the share of your benefits, not your tax bill: that depends on your deductions and brackets, and some states also tax benefits, with their own rules. Railroad retirement tier 1 benefits are handled the same way on Form RRB-1099 but you should check the form. Entries for foreign earned income exclusions and certain Puerto Rico income that Publication 915 adds on line 5 are not included, so enter them in the other-income field if they apply to you.

An estimate for planning only — not tax advice; your tax return decides. Sources, checked October 28, 2026: IRS Publication 915, “Social Security and Equivalent Railroad Retirement Benefits” (2025 edition), base amounts, Worksheet 1 and the lump-sum election. Related: Social Security calculator, Social Security break-even calculator, RMD calculator, Roth conversion tax calculator and income tax calculator. How we check our calculators.