Self-Employment Tax in 2026: The 15.3% Every Freelancer Needs to Know
How US self-employment tax works in 2026: Social Security 12.4%, Medicare 2.9%, additional Medicare surtax 0.9%, the wage base cap, and the half-deduction adjustment.
Quick Answer
Self-employment tax in the US is 15.3% (12.4% Social Security + 2.9% Medicare) on net self-employment earnings up to the Social Security wage base ($168,600 in 2024, indexed annually). Medicare has no cap and adds an additional 0.9% on income above $200k single / $250k joint. SE tax is on top of regular federal income tax. Half the SE tax is deductible as an above-the-line adjustment on Form 1040 Schedule 1.
The first time a US freelancer sees their tax bill, the question is always the same: "Why am I paying so much more than I would as an employee?" The answer is self-employment tax — the often-overlooked 15.3% that catches every Schedule C filer, partnership member, and gig worker by surprise.
This guide explains exactly how SE tax works, what counts, what doesn't, and how S-corp election dramatically reduces it.
What SE tax actually is
When you work as a W-2 employee, you pay 7.65% FICA (6.2% Social Security + 1.45% Medicare) on your wages. Your employer pays a matching 7.65%. Combined: 15.3% goes into Social Security and Medicare from every dollar of your wage (up to the wage base).
When you're self-employed, you are both the employee and the employer. So you pay the full 15.3% yourself. That's self-employment tax.
| Component | Rate | Cap (2024) |
|---|---|---|
| Social Security | 12.4% | First $168,600 |
| Medicare | 2.9% | No cap |
| Additional Medicare (high earners) | +0.9% | Above $200k single / $250k joint |
The .9235 multiplier (and the half deduction)
SE tax is calculated on net SE earnings × 0.9235 — a small adjustment that approximates the employer-paid FICA you would have received as a W-2 employee.
Example: $100,000 net Schedule C profit.
- SE tax base: $100,000 × 0.9235 = $92,350
- Social Security: 12.4% × $92,350 = $11,451 (under wage base, full amount applies)
- Medicare: 2.9% × $92,350 = $2,678
- Total SE tax: $14,129
You then get to deduct half of the SE tax ($7,065) as an above-the-line adjustment on Schedule 1, reducing your federal AGI for income tax purposes. This roughly equates to the deduction you'd get on the employer-paid FICA at a W-2 job.
How SE tax stacks with income tax
SE tax is on top of regular federal income tax — they're separate. A freelancer with $100k profit at the 22% federal income tax bracket pays:
| Item | Amount |
|---|---|
| SE tax (calculated above) | $14,129 |
| AGI after half SE deduction | $92,935 |
| Federal income tax (single, ~22% effective, 2024) | ~$15,000 |
| Total federal tax | ~$29,129 |
Plus state income tax (varies). At $100k income, a freelancer in California faces another ~$6,000 state tax, putting total tax around 35% before any deductions or credits.
What counts as SE income
SE tax applies to:
- Schedule C net business income (sole prop, single-member LLC default)
- Form 1065 K-1 ordinary business income for general partners (limited partners excluded for most income)
- 1099-NEC contractor income (reported on Schedule C)
- Side gig and platform income (Uber, DoorDash, Etsy, freelance writing, etc.)
SE tax does NOT apply to:
- W-2 wages (FICA already withheld separately)
- S-corp K-1 distributions (the savings — see below)
- Investment income (dividends, capital gains)
- Rental income (unless real estate professional)
- Limited partner K-1 distributions (with caveats)
The S-corp election: cut SE tax dramatically
This is the single biggest tax planning tool for profitable freelancers and consultants. Elect S-corp tax treatment (file Form 2553 within 75 days of qualifying), then split your business income into two parts:
- Reasonable W-2 wage — subject to FICA (15.3%)
- K-1 distribution — NOT subject to FICA
Worked example: $150,000 net business income.
As Schedule C / sole prop
- SE tax: ~$21,194 (per the calculation above, scaled)
As S-corp with $80k W-2 wage + $70k K-1
- FICA on $80k wage: $12,240 (7.65% × 2)
- FICA on $70k K-1: $0
- Saving: ~$8,954 per year
The IRS requires "reasonable compensation" — you can't pay yourself $1 W-2 and $149,999 K-1. But within reasonable bounds, the savings are real and significant.
Quarterly estimated tax — pay it or pay penalties
The IRS doesn't wait until 15 April for SE tax. Self-employed people must pay quarterly estimated tax via Form 1040-ES:
| Quarter | Period | Due |
|---|---|---|
| Q1 | 1 Jan – 31 Mar | 15 April |
| Q2 | 1 Apr – 31 May | 15 June |
| Q3 | 1 Jun – 31 Aug | 15 September |
| Q4 | 1 Sep – 31 Dec | 15 January (next year) |
(Note: the "quarters" are not equal calendar quarters — they're 3, 2, 3, 4 months long.)
Underpayment triggers Form 2210 penalty calculated as IRS short-term rate + 3% (~8%) on the shortfall. Avoid by hitting safe harbor: 90% of current year tax OR 100% of prior year (110% if prior AGI > $150k).
Common mistakes
- Setting aside only enough for income tax, forgetting SE tax. A $100k freelancer needs to set aside ~$30k+, not the ~$15k their tax bracket suggests.
- Not making quarterly payments. Penalty is calculated quarter-by-quarter — paying the full year on 15 April doesn't avoid it.
- Ignoring the additional Medicare surtax. The extra 0.9% kicks in at $200k single / $250k joint.
- Treating reimbursements as income. Client reimbursing your travel doesn't count as SE income (it's not earnings).
- Forgetting that S-corp distribution income still has income tax. S-corp election saves FICA but K-1 still attracts federal income tax.
Self-employed health insurance — a related deduction
Self-employed people can deduct 100% of health, dental and qualified long-term care insurance premiums for themselves, spouse and dependents as an above-the-line adjustment on Schedule 1, even if they don't itemize. This reduces federal income tax (not SE tax). For families paying $20k+ in premiums, it's a significant offset.
S-corp shareholders need premiums paid through the S-corp and added to W-2 Box 1, then deducted on Schedule 1 — a slightly more complex flow.
How AccountsOS handles SE tax
AccountsOS is live in the US and runs federal tax planning natively:
- Tracks Schedule C net SE income in real time
- Calculates running SE tax estimate as transactions land
- Computes optimal quarterly estimated payment for safe harbor
- Models S-corp election break-even based on your profit projection
- Generates 1099-NEC reporting for contractors $600+ paid
State income tax coverage is roadmapped; for state-specific planning, work with a state CPA.
Try AccountsOS free or read about AccountsOS in the United States.
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