The Self-Employment Tax Calculator computes the FICA taxes owed by sole proprietors, independent contractors, freelancers, single-member LLC owners, and partners in partnerships. Unlike employees — who split Social Security and Medicare taxes 50/50 with their employer — self-employed individuals pay both the employer and employee shares, creating a combined SE tax rate of 15.3% on net self-employment earnings.

SE tax is separate from federal income tax. It is calculated on Schedule SE (Form 1040) and must be paid in addition to income tax — a fact that surprises many first-year freelancers who budget only for their income tax bracket rate. A consultant netting $80,000 from their practice owes approximately $11,304 in SE tax on top of their income tax liability.

Who pays self-employment tax? According to the Social Security Administration, any individual with net self-employment earnings of $400 or more in a tax year must file Schedule SE and pay SE tax. This covers:

• Freelancers and independent contractors — receiving 1099-NEC income from clients
• Sole proprietors — reporting business profit on Schedule C
• Partners — with distributive share of partnership ordinary income (not limited partners receiving only capital distributions)
• Single-member LLC owners — taxed as sole proprietors by default
• Gig economy workers — Uber, DoorDash, TaskRabbit, Fiverr, Upwork, and similar platforms
• Farm operators — with net farm income above $400 or using the farm optional method

The good news: two built-in deductions significantly reduce the real cost of SE tax. First, only 92.35% of net self-employment earnings are subject to SE tax, because the IRS allows you to subtract the employer-equivalent portion (7.65%) before applying the rate. Second, you may deduct 50% of the SE tax paid as an above-the-line deduction on Form 1040, reducing your AGI and your income tax liability. These two adjustments together mean the effective economic burden of SE tax is noticeably lower than the headline 15.3% rate.

The official SE tax calculation follows IRS Schedule SE instructions and involves three sequential steps:

Why 92.35%? The 92.35% factor equals (1 − 0.0765). When you are employed, your employer pays 7.65% of your wages as their share of FICA before reporting your wages to the IRS. As a self-employed person, your full profit is your "gross wage equivalent," but the IRS allows you to back out the employer share (7.65%) when determining your net earnings base, consistent with how employee wages are structured. This is why $100,000 of net profit produces $92,350 of SE-taxable income, not $100,000.

2025 Rates and Limits (per SSA COLA Fact Sheet):

• Social Security (OASDI) rate: 12.4% on SE income up to $176,100
• Medicare (HI) rate: 2.9% on all SE income (no wage base cap)
• Additional Medicare Tax: 0.9% on SE income above $200,000 (single) / $250,000 (MFJ)
• Combined rate below $176,100: 15.3%
• Combined rate above $176,100: 2.9% (no SS) or 3.8% if above Additional Medicare threshold

Illustrative Example — Freelance Designer, $75,000 Net Profit:

• SE Income: $75,000 × 0.9235 = $69,262.50
• SE Tax: $69,262.50 × 0.153 = $10,597.16
• Deductible half: $10,597.16 × 0.50 = $5,298.58 (reduces AGI)
• Income tax savings from deduction (at 22%): $5,298.58 × 0.22 = $1,165.69
• Net economic cost of SE tax: $10,597.16 − $1,165.69 = $9,431.47

1. Enter your net self-employment profit. This is your gross business income minus allowable business deductions — the figure from Schedule C Line 31, or your partnership K-1 Box 14 Code A. Do not enter gross revenue; SE tax is on profit, not sales. If you have multiple businesses (e.g., consulting and real estate), combine net profits (but not losses from passive activities) across Schedule C entities.
2. Select your filing status and total income. Filing status affects the Additional Medicare Tax threshold ($200,000 for single filers; $250,000 for MFJ). If you also have W-2 wages, your SE earnings and W-2 earnings are combined to determine whether you've exceeded the $176,100 Social Security wage base — an important consideration for high earners with both employee and self-employment income.
3. Account for W-2 wages in the Social Security cap calculation. If you also received W-2 wages in 2025 on which Social Security taxes were withheld, the SS wage base is shared between your W-2 wages and your SE income. Example: if you earned $130,000 in wages and $80,000 in SE profit (SE income = $73,880), only $46,100 of SE income is subject to the 12.4% Social Security tax ($176,100 − $130,000). The calculator handles this automatically when you enter your W-2 income.
4. Review the SE tax total and the deductible half. The calculator will display (a) SE taxable income after the 92.35% adjustment, (b) the Social Security portion, (c) the Medicare portion, (d) any Additional Medicare Tax, (e) total SE tax, and (f) the deductible half — the amount you'll enter on Schedule 1 Line 15 of your Form 1040 as an above-the-line deduction.
5. Factor SE tax into your quarterly estimated payments. The IRS requires self-employed individuals to prepay both income tax and SE tax through quarterly estimates. Your total estimated tax for each quarter = (projected income tax + projected SE tax) ÷ 4. Underpaying causes a penalty equal to the federal short-term rate plus 3%. Use IRS Form 1040-ES worksheets as a guide.
6. Consider electing S corporation status if SE income consistently exceeds $50,000. An S corp allows you to pay yourself a "reasonable salary" (subject to FICA) and take remaining profit as a distribution (not subject to SE tax). At $100,000 net profit, a $60,000 salary + $40,000 distribution saves approximately $6,120 in SE tax annually ($40,000 × 15.3%) minus the cost of payroll administration (~$1,500–$2,500/year). This strategy requires careful compliance with IRS reasonable compensation standards.

Worked Example — Consultant with W-2 and 1099 Income:

• W-2 wages: $100,000 (SS already withheld on full amount)
• Schedule C net profit: $50,000
• SE income: $50,000 × 0.9235 = $46,175
• SS base remaining: $176,100 − $100,000 = $76,100 → SS applies to $46,175 (under cap)
• SS portion: $46,175 × 0.124 = $5,725.70
• Medicare portion: $46,175 × 0.029 = $1,339.08
• Total SE tax: $7,064.78
• Deductible half: $3,532.39 (reduces AGI on Form 1040)

Self-employment tax interacts with income tax in ways that compound quickly at higher income levels. Understanding the full picture — not just the SE tax figure in isolation — is essential for accurate financial planning.

SE Tax and Income Tax Are Additive

A self-employed individual in the 22% income tax bracket and earning $80,000 net profit faces a combined federal marginal burden of approximately 22% + 15.3% × 92.35% = roughly 36.1% on the next dollar of profit (partially offset by the deductible half). This is why sole proprietors with strong cash flow often feel undertaxed at the source — their W-2 counterparts have taxes automatically withheld, but freelancers must proactively set aside 25–35% of net income for federal taxes.

The Break-Even on S Corp Election

Because S corp distributions bypass SE tax, the strategy becomes financially compelling at higher income levels. The crossover point is generally considered to be $50,000–$60,000 of annual net SE profit after accounting for: payroll processing fees ($100–$250/month), state filing fees, additional accounting complexity, and the requirement to maintain payroll tax deposits. Below that level, the administrative cost typically exceeds the SE tax savings. Above $100,000, the savings are substantial and persistent year-over-year.

Additional Medicare Tax Exposure

Self-employed individuals must also self-report the 0.9% Additional Medicare Tax on Form 8959 when combined wages, compensation, and net SE income exceed the threshold. Importantly, the Additional Medicare Tax is not reduced by the 92.35% adjustment or offset by the deductible-half provision — it applies to the full excess amount above the threshold. A single filer earning $250,000 in SE profit owes the 0.9% on the $50,000 above the $200,000 threshold, adding $450 to their federal bill.

Impact on Retirement Account Contribution Limits

SE income drives the maximum allowable contribution to a SEP-IRA, Solo 401(k), and SIMPLE IRA. For a SEP-IRA, the contribution limit is 25% of net earnings from self-employment — where "net earnings" equals net profit minus the deductible half of SE tax. On $100,000 of net profit, the SEP-IRA deductible contribution is approximately $18,587 (25% of $74,348 adjusted net earnings). A Solo 401(k) allows an additional employee elective deferral of up to $23,500, making it the most powerful retirement savings vehicle for high-earning self-employed individuals. See IRS guidance on self-employed retirement contributions.

State SE Tax

Federal SE tax is entirely separate from state income tax. No state imposes a separate "SE tax" — instead, self-employment income is simply included in your state taxable income (from your federal Schedule C or K-1) and taxed at applicable state rates. In high-tax states like California (up to 13.3%), New York (up to 10.9%), or New Jersey (up to 10.75%), the combined federal + state marginal burden on SE income can exceed 50% at high income levels.

• Elect S corporation status when net SE profit consistently exceeds $50,000. Splitting income between a reasonable W-2 salary and an S corp distribution removes the distribution from SE tax entirely. At $150,000 net profit with a $90,000 salary, you pay SE tax only on the $90,000 wage base — saving roughly $9,180 in SE tax on the $60,000 distribution ($60,000 × 15.3%). The IRS requires the salary to be "reasonable" for the services performed; underpaying can trigger recharacterization. The IRS S Corporation resource page outlines the election process via Form 2553.
• Maximize deductible business expenses to reduce net SE profit. Every dollar of legitimate business expense reduces not only income tax but also SE tax. A $1,000 home office deduction for a 22% bracket taxpayer saves $220 in income tax plus $141 in SE tax (92.35% × 15.3%) — a combined $361 in federal tax savings. Deductible expenses include: home office (Form 8829 or simplified method at $5/sq ft up to 300 sq ft), vehicle mileage at 70 cents/mile (2025 IRS standard rate), self-employed health insurance premiums (100% deductible above-the-line), business meals (50%), professional development, software, and equipment.
• Contribute to a SEP-IRA or Solo 401(k) to reduce SE-taxable income at the business level. Wait — retirement contributions reduce income tax but do not reduce SE tax (SE tax is based on Schedule C profit, not AGI). However, the self-employed health insurance deduction does reduce SE income if structured as a partnership benefit. Regardless, Solo 401(k) and SEP-IRA contributions dramatically reduce income tax at the 22–37% bracket level, making after-tax retirement funding far cheaper than it appears.
• Hire your spouse legitimately and pay a reasonable wage. If your spouse provides genuine services, you can pay them a W-2 wage from your sole proprietorship. That wage is subject to payroll FICA at 15.3% (same as SE tax) but allows the spouse to contribute to a 401(k) and potentially opens access to employer-sponsored health insurance. More importantly, hiring minor children in a sole proprietorship avoids FICA taxes entirely on their wages (children under 18 are exempt from FICA in a sole proprietorship), and children's standard deduction shelters the first $15,000 of earned income from federal income tax in 2025.
• Track the SS wage base cap across multiple income sources. If you have W-2 income plus SE income and your combined earnings exceed $176,100, you will overpay Social Security taxes if you don't account for the cap. W-2 employers withhold without knowing about your SE income. The excess SS overpayment appears as a refundable credit on your Form 1040 (Schedule 3 Line 11) — but only if you file correctly and claim it. Many self-employed workers with both W-2 and 1099 income leave this credit on the table.
• Time year-end invoicing to manage taxable profit in transition years. If you expect to earn significantly less in 2026 (dropping from the 24% to 22% bracket, for example), delay issuing December invoices until January 2026. The $2,000 difference in income tax (22% vs 24% on the shifted income) plus $306 in SE tax savings on a $10,000 invoice deferral could total $2,306 in federal tax savings — simply by controlling the timing of a client payment. This strategy is most effective for cash-basis taxpayers, which most sole proprietors are by default.