Federal Retirement Income Tax Calculator 2026

Retirement income taxes are more complex than most people expect. Social Security is taxed on a sliding formula based on "provisional income." RMDs are ordinary income — but QCDs are excluded entirely. The 2026 deduction stack has three layers for retirees 65 and older. Enter your numbers below to see exactly how your income flows through the federal tax calculation.

This calculator covers federal income tax only. For Medicare surcharges, use the IRMAA Calculator. For state tax, use the State Retirement Income Tax Calculator.

How the calculation works

Step 1 — Social Security provisional income

The IRS uses "provisional income" (PI) to determine how much of your Social Security benefit is subject to federal tax. PI is not the same as AGI: it equals your non-SS income plus half of your gross Social Security benefit.¹

The thresholds have never been adjusted for inflation — which is why nearly 90% of higher-income retirees now have 85% of their Social Security in taxable income:

A retiree with an $80,000 RMD and $36,000 in Social Security has provisional income of $98,000 ($80,000 + $18,000). That's well above $44,000 — so 85% of the $36,000 SS benefit ($30,600) enters AGI. The actual SS check doesn't change; what changes is how much is included in taxable income.

Step 2 — Adjusted Gross Income

Once you know how much of your Social Security is taxable, your AGI assembles as:

• Taxable Social Security (0%, 50%, or up to 85% of the gross benefit)
• RMD amount, minus any QCDs (QCDs exit income entirely — they never appear in AGI)
• Pension and annuity income
• Other ordinary income

Step 3 — The 2026 retirement deduction stack

Retirees 65 and older benefit from three layers of deduction in 2026:²³

The OBBBA senior deduction is new for 2025–2028. At $6,000 per person 65+, it substantially reduces retirement income taxes for couples below the phaseout range — but it begins phasing out at 6 cents per dollar of AGI above $75,000 (single) or $150,000 (MFJ), and disappears entirely by $175,000 (single) or $250,000 (MFJ).

Step 4 — 2026 federal tax brackets on taxable income

After deductions, taxable income flows through the 2026 brackets. These are marginal rates — only income in each bracket pays that rate:²

Strategies to reduce your 2026 federal retirement tax

Qualified Charitable Distributions (QCDs): the highest-leverage tool

If you're 70½ or older and charitable, QCDs reduce income at every level simultaneously. A $20,000 QCD: (1) satisfies $20,000 of your RMD requirement, (2) removes $20,000 from AGI, (3) lowers provisional income — which may move some Social Security from 85%-taxable to a lower tier, (4) reduces your OBBBA phaseout exposure, and (5) reduces IRMAA MAGI two years forward. No other single planning move affects all five levers at once. The 2026 limit is $111,000 per IRA owner.⁴

Roth conversions before RMD age

Every dollar converted from a traditional IRA to Roth before age 73 permanently reduces future RMDs — and therefore permanently reduces future provisional income. A couple who converts $50,000/year from age 65 to 72 can drop their RMD at 73 from $100,000+ to $50,000, keeping Social Security partially out of the 85% zone and staying below the IRMAA Tier 1 threshold. The conversion year tax is higher; every year after is lower. See the Roth Conversion Calculator for a lifetime comparison.

IRMAA: the 2026 Medicare connection

Your 2026 federal income tax and your 2028 Medicare IRMAA surcharges are driven by the same number: 2026 MAGI. A single filer whose 2026 AGI exceeds $109,000 faces IRMAA surcharges of $1,148/year or more in 2028. Planning both taxes together — not separately — is how integrated retirement tax planning works. Use the IRMAA Calculator to see your Medicare surcharge on top of today's federal tax estimate.

Sources

1. IRS Publication 915 — Social Security and Equivalent Railroad Retirement Benefits. Provisional income formula, 50%/85% SS taxation tiers, and thresholds ($25K/$34K single; $32K/$44K MFJ). Thresholds are not indexed to inflation. Verified June 2026.
2. IRS Revenue Procedure 2025-32. 2026 tax brackets: single 10%→$12,400, 12%→$49,400, 22%→$105,700, 24%→$201,775, 32%→$256,225, 35%→$640,600; MFJ 10%→$24,800, 12%→$98,800, 22%→$211,400, 24%→$403,550, 32%→$512,450, 35%→$768,600. Standard deduction single $16,100 / MFJ $32,200. Additional deduction 65+: $2,050 single / $1,650 per MFJ spouse.
3. IRS — One Big Beautiful Bill Act: Tax deductions for seniors. OBBBA senior deduction: $6,000 per person age 65+ (effective 2025–2028). Phases out at 6% per dollar of MAGI above $75,000 (single) / $150,000 (MFJ); fully phased out at $175,000 (single) / $250,000 (MFJ). Available to both itemizers and non-itemizers.
4. Charles Schwab — Reducing RMDs With QCDs in 2026. 2026 QCD limit: $111,000 per IRA owner (inflation-adjusted). QCDs exclude the distributed amount from AGI entirely; not merely a deduction. Direct-transfer requirement from IRA to qualified 501(c)(3) charity. Available from age 70½.

Tax values verified against IRS Rev. Proc. 2025-32, IRS OBBBA newsroom, and Schwab 2026 QCD guidance, June 2026. This calculator is an educational estimate — not a substitute for professional tax preparation. Actual tax may differ based on additional income, itemized deductions, AMT, NIIT, state taxes, and other factors.