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Social Security Tax Calculator

Enter your Social Security benefit, other income, and filing status to find exactly how much of your benefit is subject to federal tax.

Updated July 2026 · Figures verified July 2026 (sources) · Editorial standards

Your Income

$
$
$
Taxable SS Benefit
$11,300.00
% of Benefit Taxable
47%
Provisional Income
$42,000.00
Est. Federal Tax on SS
$1,356.00

47% of your SS benefit — $11,300.00 — is taxable. Provisional income: $42,000.00. Estimated federal tax on SS: $1,356.00.Reducing other taxable income (e.g., Roth withdrawals instead of traditional IRA) can lower the taxable portion.

By KalkWiseVerified against official sources Updated July 2026

What is the social security tax calculator — how much is taxable??

In short

A single retiree with $24,000 in Social Security benefits and $30,000 in other income has a provisional income of $42,000 — above the $34,000 upper threshold. Up to 85% of the $24,000 benefit ($20,400) is taxable, resulting in approximately $2,448 in federal tax attributable to Social Security.

This Social Security tax calculator applies the IRS provisional income test to determine what percentage of your Social Security benefits (0%, up to 50%, or up to 85%) is subject to federal income tax. It uses 2026 IRS thresholds and estimates the federal tax attributable to the taxable portion.

How to use this calculator

  1. 1Enter your total annual Social Security benefit (all benefits received during the year).
  2. 2Enter your other income: wages, pensions, IRA withdrawals, dividends, and any other taxable income excluding Social Security.
  3. 3Enter any tax-exempt interest income from municipal bonds — this counts toward provisional income.
  4. 4Select your filing status and read your provisional income, taxable SS amount, and estimated tax on SS.

The formula

PI=AGI+TEI+0.5×SS
taxableSS=min(SS×0.85,f(PI))
Provisional income = AGI + tax-exempt interest + 50% of SS benefits. Single filers: if PI ≤ $25,000, SS is not taxable; if $25,000–$34,000, up to 50% is taxable; above $34,000, up to 85% is taxable. For married filing jointly: thresholds are $32,000 and $44,000. Married filing separately: 85% is always taxable.
PI
— Provisional income (combined income)
SS
— Annual Social Security benefit
AGI
— Other adjusted gross income (excluding SS)
TEI
— Tax-exempt interest income

Worked example

The scenario

Single filer, $24,000 SS benefit, $30,000 other income, $0 tax-exempt interest.

gives

The result

Provisional income = $30,000 + $0 + $12,000 (50% of SS) = $42,000. Above $34,000 threshold: 85% of SS is taxable. Taxable SS = $20,400. Estimated federal tax on SS ≈ $2,448 (at 12% marginal rate on the additional $20,400). Effective SS tax rate = 10.2%.

Common use cases

  • Planning withdrawals from traditional IRAs to stay below the SS taxability threshold.
  • Deciding whether Roth conversions before claiming SS can reduce lifetime SS taxes.
  • Comparing total tax cost of claiming SS at 62 vs. delaying to 67 or 70.
  • Understanding how part-time work or pension income affects SS taxability.

Limitations & assumptions

  • Calculates federal income tax only — Social Security itself is not subject to FICA/payroll tax.
  • State taxation of SS benefits varies: 11 states tax SS; 39 states and DC do not. Not modeled here.
  • Uses 2026 thresholds ($25k/$34k single, $32k/$44k MFJ) — these thresholds are not indexed for inflation and have not changed since 1994.
  • The estimated tax on SS uses 2026 single-filer brackets; for married filers the actual tax will differ.

Frequently asked questions

For single filers, SS benefits begin to be taxable when provisional income exceeds $25,000. Above $34,000, up to 85% of benefits are taxable. For married filing jointly, the thresholds are $32,000 and $44,000. These limits have not changed since 1984 and 1993, meaning more retirees become subject to SS tax each year due to inflation.

Disclaimer: KalkWise calculators are provided for general informational and educational purposes only and do not constitute financial, investment, tax, or legal advice. Results are estimates based on the figures you enter and the assumptions described above. Actual outcomes will vary. Consult a qualified professional before making financial decisions.