Step 1: calculate provisional income
Provisional income = your adjusted gross income (excluding Social Security) + tax-exempt interest + half of your Social Security benefits. This number decides how much of your benefit is taxable.
| Filing status | No benefits taxed | Up to 50% taxed | Up to 85% taxed |
|---|---|---|---|
| Single, head of household, qualifying surviving spouse | Below $25,000 | $25,000 to $34,000 | Above $34,000 |
| Married filing jointly | Below $32,000 | $32,000 to $44,000 | Above $44,000 |
| Married filing separately (lived with spouse) | — | — | Almost always up to 85% |
These thresholds are set by law and are not adjusted for inflation, so more retirees become taxable over time.
Worked example (single filer)
Benefits $24,000 and other income $30,000. Provisional income = $30,000 + $12,000 (half of benefits) = $42,000, which is above $34,000. Taxable benefits are the lesser of 85% of benefits ($20,400) or 85% of the amount over $34,000 ($6,800) plus $4,500, which is $11,300. About 47% of the benefit is taxable, and that amount is taxed at your regular rate. IRS Publication 915 has the full worksheet.
The $6,000 senior deduction
For tax years 2025 through 2028, each taxpayer who is 65 or older by year-end can claim an extra $6,000 deduction ($12,000 for a couple where both qualify), on top of the standard deduction. It phases out by 6% of income above $75,000 (single) or $150,000 (joint) and requires a valid Social Security number.
| 2026 standard deduction | Base | Extra if 65 or older |
|---|---|---|
| Single | $16,100 | +$2,050 |
| Married filing jointly | $32,200 | +$1,650 each spouse |
Other things to know
- Withholding: you can ask SSA to withhold federal tax from your benefits using Form W-4V at 7%, 10%, 12%, or 22%.
- State taxes: most states do not tax Social Security benefits, but a few do. Check your state's rules.
- Medicare premiums: higher income can also trigger IRMAA surcharges two years later.