Tax Obligation Calculator 2026 — How Much Federal Tax Do You Owe?
Your tax obligation is the total federal tax you owe for the year, before subtracting anything already withheld from your paychecks. It's a different number from your refund or balance due. Use the form below to estimate your full 2026 obligation: income tax plus FICA, self-employment tax (if any), and the 0.9% Additional Medicare on high wages.
Calculate your federal tax obligation
Your 2026 Federal Tax Obligation
What "tax obligation" actually means
The IRS uses three related numbers that people often mix up. Your total tax liability (line 24 of Form 1040) is your obligation: every dollar of federal tax you owe for the year. Tax withheld (line 25) is what's already come out of your paychecks via the W-4 you filled out, plus any 1099 withholding or estimated payments. The difference between those two — refund or amount owed (lines 34 or 37) — is what shows up on April 15. The obligation is the bigger, more important number, because that's the real cost of being a US taxpayer this year. The refund-vs-owed line is just whether you over- or under-paid in advance.
The 2026 obligation has up to five components
Federal income tax (ordinary). Wages, interest, ordinary dividends, short-term capital gains, and most retirement withdrawals are taxed at the seven progressive 2026 brackets: 10%, 12%, 22%, 24%, 32%, 35%, 37%. Each rate applies only to the income inside that band. A single filer with $75,000 taxable income hits the 22% marginal bracket but pays an effective federal income tax rate around 13–14%.
Long-term capital gains and qualified dividends. Assets held over a year, plus qualified dividends, are taxed separately at 0%, 15%, or 20% based on total taxable income. For 2026, the 0% bracket runs up to $49,400 single / $98,750 MFJ. Above $544,050 single / $612,350 MFJ, the top 20% rate applies.
FICA payroll taxes. W-2 employees pay 6.2% Social Security on the first $184,500 of wages plus 1.45% Medicare on every dollar — 7.65% total. The employer matches that, but the employee match is invisible on a payslip even though it ultimately comes out of the labour-market wage. For obligation purposes, count only the employee 7.65%.
Self-employment tax. If you have 1099 or Schedule C income, you pay both the employee and employer halves of FICA on 92.35% of net SE earnings. The combined rate is 15.3% (12.4% Social Security up to the wage base + 2.9% Medicare unlimited). Half of the SE tax is deductible as an adjustment to income, which slightly lowers your ordinary income tax.
Additional Medicare Tax. A 0.9% surtax on wages and SE earnings above $200,000 single / $250,000 MFJ / $125,000 MFS. Employers withhold it on wages above $200,000 regardless of filing status, but you reconcile the actual obligation on Form 8959 with your return.
Worked example — single filer, $80,000 W-2 wages
Wages $80,000, no other income, single, standard deduction. Taxable income = $80,000 − $15,350 = $64,650. 2026 single ordinary tax: 10% × $12,150 + 12% × $37,325 + 22% × $15,175 = $1,215 + $4,479 + $3,338.50 = $9,032.50. FICA: 7.65% × $80,000 = $6,120. No SE tax, no Additional Medicare. Total obligation = $15,152.50 (about 18.9% of gross). The refund or owed amount at April 15 depends on how much was withheld during the year.
Worked example — freelancer with $90,000 Schedule C net
Net SE income $90,000, single, standard deduction. SE tax: 15.3% × ($90,000 × 0.9235) = 15.3% × $83,115 = $12,716.60. Half ($6,358.30) is deductible above the line. AGI = $90,000 − $6,358.30 = $83,641.70. Taxable income = $83,641.70 − $15,350 = $68,291.70. Ordinary tax: 10% × $12,150 + 12% × $37,325 + 22% × $18,816.70 = $1,215 + $4,479 + $4,139.67 = $9,833.67. No FICA (already in SE tax). No Additional Medicare (under $200k). Total obligation = $22,550.27 — exactly why quarterly estimated payments matter.