FICA & Social Security Tax Calculator
Calculate your Social Security and Medicare taxes for 2025 or 2024. See the full employee vs employer split, self-employment tax details, and a rough estimate of your future monthly Social Security benefit.
Your FICA (Employee)
$5,738Total FICA (Both Sides)
$11,475Est. Monthly SS Benefit
$2,500| Item | Amount |
|---|---|
| SS Wage Base (2025) | $176,100 |
| SS Taxable Wages | $75,000 |
| SS Rate (each side) | 6.20% |
| Employee SS Tax | $4,650.00 |
| Employer SS Tax | $4,650.00 |
| Total SS Tax | $9,300.00 |
| Item | Amount |
|---|---|
| Medicare Rate (each side) | 1.45% |
| Base Medicare Tax (per side) | $1,087.50 |
| Total Medicare Tax | $2,175.00 |
| Tax | Employee | Employer | Total |
|---|---|---|---|
| Social Security | $4,650.00 | $4,650.00 | $9,300.00 |
| Medicare | $1,087.50 | $1,087.50 | $2,175.00 |
| Total FICA | $5,737.50 | $5,737.50 | $11,475.00 |
This is a rough estimate based on your current income. Actual benefits depend on your full earnings history, age at claiming, and other factors. Visit ssa.gov for a personalized estimate.
Estimated Monthly Benefit
$2,500
Estimated Annual Benefit
$30,000
How FICA tax works: the four components
FICA (Federal Insurance Contributions Act, 26 U.S.C. §3101–§3128) funds two different federal entitlements with very different rules. Social Security tax (OASDI — Old-Age, Survivors and Disability Insurance) is capped by an annual wage base; Medicare (Hospital Insurance) is uncapped. Two extra layers — the 0.9% additional Medicare surtax and the self-employment reconciliation — finish the picture.
1. Social Security (OASDI) — 6.2%
Withheld from each paycheck on gross wages up to the annual wage base ($176,100 in 2025, $184,500 in 2026). Once your cumulative year-to-date wages cross the base, no further Social Security tax is withheld until the new year resets on 1 January.
2. Medicare (Hospital Insurance) — 1.45%
Withheld at 1.45% on every dollar of wages with no cap. Employers match it dollar-for-dollar. There is no annual reset and no wage-base ceiling.
3. Additional Medicare Tax — 0.9%
An extra surtax on earned income above $200,000 single / $250,000 MFJ / $125,000 MFS. Employers withhold the 0.9% from YOUR wages above $200,000 regardless of filing status — the household reconciliation happens on Form 8959 at filing time. Employer does NOT match the 0.9%.
4. Self-Employment tax — 15.3%
Self-employed earners pay both halves of FICA — employee AND employer — for a combined 15.3% (the 7.65% employee + 7.65% employer adds to 15.3%). Only 92.35% of net SE profit is subject to SE tax, and 50% of the SE tax paid is deductible above-the-line on Schedule 1.
Employee vs employer: who pays what
For W-2 wages, FICA is split exactly evenly between employee and employer — with one important exception (the 0.9% additional Medicare surtax) where the employer doesn't match. For self-employed earners, both halves land on the same person — but they get to deduct the employer-equivalent half from income tax. Pre-tax payroll deductions further reshape the base.
| Tax component | Employee pays | Employer pays | Self-employed pays |
|---|---|---|---|
| Social Security (OASDI) | 6.2% | 6.2% | 12.4% |
| Medicare (HI) | 1.45% | 1.45% | 2.9% |
| Additional Medicare (over $200k single) | 0.9% | — | 0.9% |
| Combined FICA / SE | 7.65% (+ 0.9% high) | 7.65% | 15.3% (+ 0.9% high) |
Most pre-tax payroll deductions bypass FICA: HSA via payroll, Section 125 cafeteria-plan health insurance, dependent-care FSA, medical FSA, commuter benefits. Traditional 401(k) and 403(b) deferrals do NOT bypass FICA — they save federal and state income tax but not the 7.65% payroll tax. That asymmetry is why HSA + 401(k) are usually stacked rather than treated as substitutes.
Self-employment FICA: Schedule SE in four steps
Self-employed taxpayers handle FICA via Schedule SE attached to Form 1040. The math is a four-step adjustment that converts net business profit into an SE-taxable base, applies the combined rate, then refunds half via an income-tax deduction.
- 1. Start with net profit from Schedule C (or Schedule F for farming). Gross receipts minus business expenses. Wages from a W-2 job do NOT count here — those already paid FICA through payroll.
- 2. Multiply by 92.35% to get the SE-taxable base. The 7.65% reduction is meant to mirror the deductibility employer FICA enjoys on the income-tax side. So a $100,000 net profit produces a $92,350 SE-taxable base.
- 3. Apply Social Security and Medicare at combined rates. 12.4% Social Security on the SE-taxable base up to the wage base ($176,100 for 2025) PLUS 2.9% Medicare on the entire SE-taxable base PLUS 0.9% additional Medicare on any earned income (W-2 + SE combined) above the household thresholds.
- 4. Deduct half of SE tax above-the-line. Half of the SE tax paid (excluding the 0.9% additional Medicare) goes onto Schedule 1 as an income-tax adjustment, lowering AGI. This is the employer-half symmetry: W-2 employers deduct their FICA as a business expense; self-employed taxpayers deduct it on their personal return.
The self-employment tax calculator runs all four steps from your Schedule C net profit. The quarterly estimated tax calculator schedules the payments needed to avoid the Form 2210 underpayment penalty.
Four worked examples (2025)
Numbers computed from the same engine that powers the calculator widget above. SE example uses Schedule SE's 92.35% net-earnings factor and includes both halves of the FICA rate (12.4% SS + 2.9% Medicare).
W-2 employee, $50,000
Straightforward case — all wages well below the SS wage base, no additional Medicare. Demonstrates the 7.65% baseline.
- Wages
- $50,000
- Social Security tax
- $3,100
- Medicare tax (+ 0.9% if any)
- $725
- Total FICA / SE tax
- $3,825
W-2 employee, $200,000
Crosses the $200,000 single threshold for Additional Medicare. Employer withholds the 0.9% on wages above $200k regardless of filing status.
- Wages
- $200,000
- Social Security tax
- $10,918
- Medicare tax (+ 0.9% if any)
- $2,900
- Total FICA / SE tax
- $13,818
W-2 employee, $400,000
Far above the SS wage base — Social Security taxes cap at the wage base × 6.2%; Medicare keeps going including the 0.9% additional surtax.
- Wages
- $400,000
- Social Security tax
- $10,918
- Medicare tax (+ 0.9% if any)
- $7,600
- Total FICA / SE tax
- $18,518
Self-employed, $100,000 net profit
Schedule SE: only 92.35% of net profit is subject to SE tax. The combined rate is 15.3% (employee + employer halves), and half is deductible above-the-line.
- Net SE profit
- $100,000
- Social Security tax
- $11,451
- Medicare tax (+ 0.9% if any)
- $2,678
- Total FICA / SE tax
- $14,130
- Deductible half (Schedule 1)
- −$7,065
For a W-2 employee, the employer pays a matching amount on top of the numbers above (except the 0.9% additional Medicare surtax). So the $50,000 employee's $3,825 FICA is matched dollar-for-dollar — the IRS receives a total of $7,650 between the two parties.
Where your FICA dollars actually go
The 6.2% Social Security tax funds the OASDI trust funds — Old-Age and Survivors Insurance (OASI) and Disability Insurance (DI). The 1.45% Medicare tax funds Part A (Hospital Insurance), which covers inpatient hospital stays, skilled nursing facility care, hospice, and some home health for beneficiaries. The 0.9% additional Medicare surtax flows to the Hospital Insurance trust fund. The SSA wage base is tied to the National Average Wage Index (NAWI), so it tracks wage growth rather than CPI — it tends to outpace inflation in years when wages grow faster than prices.
Your eventual Social Security retirement benefit is calculated from your 35 highest-earning years (indexed) via the Primary Insurance Amount (PIA) formula. Capping years at the wage base means earnings above the base do not increase your benefit. The Social Security benefits calculator models the PIA breakpoints and the claim-age multipliers (62 reduction, 67 full retirement age for those born 1960+, up to age-70 delayed retirement credits).
Common FICA / SE-tax mistakes
- Multi-employer over-withholding of Social Security. Each employer separately tracks the $176,100 wage base — if you worked two jobs and combined wages exceeded it, you paid too much Social Security. Recover the excess on Schedule 3 line 11 of Form 1040.
- Missing the additional 0.9% Medicare household reconciliation. Couples filing MFJ where neither paycheck individually crossed $200,000 but the combined wages exceed $250,000 still owe the surtax. Form 8959 reconciles.
- Forgetting SE tax has no standard deduction reduction. SE tax is computed on Schedule SE based on net business profit — your standard deduction and itemized deductions do NOT reduce SE tax. They reduce income tax only.
- Treating S-corp owner wages and distributions identically. S-corp shareholder-employees must take "reasonable" W-2 wages subject to FICA; distributions are NOT subject to FICA. IRS audits target unreasonably low wage levels. Use the S-corp breakeven calculator to find the FICA savings threshold.
- Skipping the half-of-SE-tax deduction. Self-employed taxpayers can deduct 50% of their SE tax above-the-line. Forgetting this overstates AGI and can push the filer over a phaseout cliff (Roth IRA, ACA PTC, IRMAA).
- Confusing the SS wage base with the additional Medicare threshold. The wage base ($176,100 in 2025) caps Social Security only. The $200,000 single / $250,000 MFJ thresholds are statutory and unindexed — they have stayed at the same nominal level since 2013.
Frequently asked questions
What is FICA tax?
FICA (Federal Insurance Contributions Act) tax funds Social Security and Medicare. Employees pay 6.2% for Social Security and 1.45% for Medicare, for a combined rate of 7.65%. Employers pay a matching 7.65%, bringing the total FICA tax to 15.3% of wages. These taxes are automatically withheld from your paycheck by your employer.
What is the Social Security wage base for 2025?
For 2025, the Social Security wage base is $176,100, meaning only the first $176,100 of your earnings are subject to the 6.2% Social Security tax. Any wages above this threshold are exempt from Social Security tax but are still subject to the 1.45% Medicare tax. The wage base is adjusted annually based on changes in the national average wage index.
What is the Additional Medicare Tax?
The Additional Medicare Tax is an extra 0.9% tax on earned income above $200,000 for single filers or $250,000 for married filing jointly. It applies on top of the standard 1.45% Medicare tax, bringing the total Medicare rate to 2.35% on high earnings. Unlike regular Medicare tax, employers do not match the Additional Medicare Tax — it is paid entirely by the employee.
How is self-employment tax different from FICA?
Self-employment tax is essentially the self-employed person's version of FICA, but you pay both the employee and employer portions for a combined rate of 15.3%. However, you only pay SE tax on 92.35% of your net self-employment income, and you can deduct the employer-equivalent half (7.65%) as an above-the-line deduction on your income tax return. The same Social Security wage base and Additional Medicare Tax thresholds apply.
Does FICA tax apply to bonuses, overtime, commissions, and tips?
Yes — all compensation paid for services is FICA wages by default. Bonus pay, commissions, overtime premiums, tips, severance, and most fringe benefits are subject to both Social Security and Medicare withholding. OBBBA-era "no tax on tips" and "no tax on overtime" are federal income-tax deductions, NOT FICA exclusions — FICA still applies. Use the bonus tax calculator for the 22% flat supplemental withholding logic.
How does the Social Security wage base get adjusted each year?
The wage base is tied to the National Average Wage Index (NAWI), not CPI. Each October the SSA publishes next-year cost-of-living updates. Because wages have grown faster than prices in most recent years, the wage base typically rises by 3–5% per year. For 2026, the wage base climbs from $176,100 in 2025 to $183,600 — about a 4.3% increase.
Do household employees and nannies owe FICA?
Yes. If you pay any household employee $2,700 or more in 2025 ($2,800 in 2026), you must withhold and remit FICA. Both halves total 15.3%. Most household employers report annually on Schedule H attached to Form 1040 rather than filing quarterly 941s. See the nanny tax calculator.
How do FICA taxes interact with 401(k), 403(b), and 457(b) contributions?
Traditional 401(k), 403(b), and 457(b) elective deferrals reduce federal AND state taxable wages, but they do NOT reduce the FICA base. You still owe 6.2% Social Security and 1.45% Medicare on the deferred amount. Roth versions of these accounts contribute post-tax — they reduce neither income-tax wages nor FICA wages.
What about HSA contributions made through payroll?
HSA contributions routed through your employer's Section 125 cafeteria plan bypass federal income tax, state income tax (in most states), AND FICA. That triple shield is the biggest tax advantage of any retirement-adjacent account. Direct HSA deposits made outside payroll get the federal-tax deduction at filing time but still pay FICA. Limits: $4,300 self / $8,550 family for 2025 — see the HSA calculator.
Is FICA refundable if I had two employers and over-paid Social Security?
Yes. Each employer separately enforces the wage base. If your combined W-2 wages from multiple employers exceeded $176,100 in 2025 you over-paid Social Security tax — the excess is claimed as a credit on Schedule 3, line 11 of Form 1040. Medicare has no cap so there's no Medicare over-payment to recover (other than the additional 0.9% reconciliation on Form 8959).
Do non-resident aliens and F-1 students pay FICA?
F-1, J-1, M-1, and Q-1 non-resident alien students working under their visa status are exempt from FICA for the first 5 calendar years in the US (IRC §3121(b)(19)). After they become resident aliens under the substantial presence test, normal FICA applies. Some bilateral totalisation agreements also exempt foreign workers temporarily assigned to the US.
Why do my FICA wages on the W-2 differ from my federal wages?
W-2 Box 1 (federal taxable wages) reflects any pre-tax deductions that reduce federal income tax — 401(k), 403(b), HSA, FSA, Section 125 health insurance. Box 3 (Social Security wages) and Box 5 (Medicare wages) only subtract the deductions that bypass FICA — HSA, Section 125, FSA. So 401(k) deferrals will make Box 1 smaller than Box 3 — the gap is your 401(k) elective deferral for the year.
Sources
Related insights
Use these guides for rule explanations, planning context, and follow-up questions beyond the calculator result.
How FICA tax works
Social Security, Medicare, wage caps, and when additional Medicare tax applies.
Understanding FICA, Social Security, and Medicare
A plain-English guide to payroll tax withholding for W-2 employees.
How self-employment tax works
Why the 92.35% factor exists and how SE tax differs from employee withholding.