Retirement Income Tax Calculator
Combine the income streams that appear on a retiree’s federal return and see taxable Social Security, estimated AGI/MAGI, federal tax and Medicare IRMAA exposure.
Estimated federal tax
$6,540Balance after withholding
$1,540Taxable Social Security
$25,500Estimated MAGI
$70,500Effective tax rate
8.7%2026 Medicare tier
Standard (no IRMAA)No IRMAA surcharge at this MAGI
This is a federal current-year estimate. Pension inputs should already reflect any tax-free basis. State retirement-income rules and Medicare’s two-year MAGI lookback require separate review.
What this estimate covers
- Combines ordinary and preferential-rate retirement income instead of treating every dollar the same.
- Shows the Publication 915 taxable-benefit result and the effect of withholding.
- Uses MAGI only as an IRMAA planning flag; Medicare applies a two-year lookback.
- Includes the additional standard deduction for filers 65 or older and the 2025–2028 senior deduction where MAGI allows.
Frequently asked questions
How is retirement income taxed federally?
Pension and pretax IRA or 401(k) distributions are generally ordinary income. Social Security uses a separate combined-income worksheet, while qualified dividends and long-term capital gains use preferential rate brackets.
Does an RMD increase the tax on Social Security?
Usually. A taxable RMD raises adjusted gross income and therefore combined income, which can cause a larger portion of Social Security benefits to become taxable.
At what income do Social Security benefits become taxable?
Taxability is driven by combined income — adjusted gross income excluding benefits, plus tax-exempt interest, plus half of benefits. For a single filer the first inclusion tier begins at $25,000 and the 85% tier at $34,000; married filing jointly uses $32,000 and $44,000. These thresholds are statutory and are not indexed for inflation, so more retirees cross them each year.
Are Roth withdrawals included in this estimate?
Qualified Roth IRA and Roth 401(k) withdrawals are not taxable income and do not enter adjusted gross income, so they do not increase taxable Social Security or the modified AGI used for IRMAA. Enter only pretax distributions in the withdrawal fields.
Why does the calculator show an IRMAA tier?
Medicare uses modified adjusted gross income from two years earlier. The result is a planning warning based on 2026 premium tiers, not a determination of a future SSA notice.
Sources
Related Calculators
Social Security Taxability
Provisional income formula, up to 85% inclusion in taxable income
Pension & Annuity Tax Calculator
IRS Simplified Method: tax-free vs taxable portion of pension/annuity payments, Pub 575 Tables 1 & 2
RMD Calculator
Required minimum distributions, age 73 RBD, life-expectancy tables
Roth Conversion IRMAA Calculator
Model a taxable Roth conversion against published Medicare IRMAA tiers and the two-year MAGI lookback