How Self-Employment Tax Works
Self-employment tax is the self-employed equivalent of FICA payroll taxes that W-2 employees share with their employers. When you work for an employer, you pay 7.65% of your wages in FICA taxes (6.2% Social Security + 1.45% Medicare), and your employer pays a matching 7.65%. When you are self-employed, you pay both halves — the full 15.3%. This applies to all net self-employment income, regardless of whether you also have W-2 income from another job.
The 15.3% rate breaks down into 12.4% for Social Security (on income up to the $176,100 wage base for 2025) and 2.9% for Medicare (on all income with no cap). An additional 0.9% Medicare surtax applies to self-employment income above $200,000 for single filers or $250,000 for married filing jointly. Before applying the 15.3% rate, your net self-employment income is multiplied by 92.35% — this adjustment compensates for the fact that W-2 employees only pay their share of FICA on their wages, not on the employer's matching contribution.
The SE Tax Deduction: How to Reduce Your Self-Employment Tax Bill
While the 15.3% SE tax rate can feel steep, the tax code provides a valuable offset: you can deduct half of your self-employment tax from your adjusted gross income. This is an above-the-line deduction, meaning you claim it on Schedule SE regardless of whether you take the standard deduction or itemize. The deduction does not reduce the SE tax itself — you still owe the full 15.3% — but it reduces the income subject to federal income tax, lowering your overall tax burden.
For a freelancer earning $100,000 in net self-employment income, the SE tax is approximately $14,130. Half of that ($7,065) can be deducted from AGI, saving roughly $1,554 to $2,614 in income tax depending on the marginal bracket. This deduction exists because W-2 employees effectively receive the same benefit — their employer's share of FICA is not counted as taxable income to the employee.
Quarterly Estimated Tax Payments for Freelancers
Unlike W-2 employees who have taxes withheld every paycheck, self-employed individuals must pay estimated taxes quarterly. The IRS expects you to pay as you earn — waiting until April to pay the full year's tax can result in underpayment penalties. Quarterly payments for the 2025 tax year are due April 15 (Q1), June 16 (Q2), September 15 (Q3), and January 15, 2027 (Q4). The simplest approach is to divide your total expected tax by four and pay equal installments.
The IRS safe harbor rule lets you avoid penalties if your quarterly payments total at least 100% of last year's tax liability (110% if your AGI exceeded $150,000) or 90% of the current year's tax. Many freelancers with variable income prefer the prior-year safe harbor because it provides certainty regardless of how much they earn this year. Make payments using IRS Direct Pay, EFTPS, or Form 1040-ES vouchers.
The QBI Deduction: A 20% Deduction for Self-Employed Workers
The Qualified Business Income (QBI) deduction allows eligible self-employed individuals to deduct up to 20% of their qualified business income from their taxable income. For a freelancer earning $80,000 in net self-employment income, the QBI deduction could be worth up to $16,000 — reducing the income tax bill by roughly $3,520 in the 22% bracket. This deduction was originally created by the Tax Cuts and Jobs Act and has been extended through the One Big Beautiful Bill.
The full 20% deduction is available when taxable income is below $191,950 (single) or $383,900 (MFJ). Above those thresholds, the deduction may be limited based on the type of business, wages paid to employees, and the value of qualified property. The calculator above uses the simplified 20% rate — consult a tax professional if your income exceeds the threshold or if you operate a specified service business.
Self-Employment vs. W-2: Total Tax Comparison
Self-employed individuals typically pay more in total tax than W-2 employees at the same income level because they cover both sides of FICA. At $80,000 of income, a W-2 employee pays $6,120 in FICA (7.65%), while a self-employed individual pays approximately $11,304 in SE tax (15.3% of 92.35%). However, the self-employed worker gets the SE deduction and QBI deduction, which partially offset the difference. After accounting for all deductions, the effective total tax rate for a self-employed single filer earning $80,000 is typically 25-28%, compared to 22-25% for an equivalent W-2 employee. The gap narrows at higher incomes where the Social Security cap kicks in.