When you work for an employer, Social Security and Medicare taxes come out of each paycheck and your employer pays a matching share. When you work for yourself, you pay both halves. The IRS calls this self-employment (SE) tax. It surprises many new freelancers, gig workers and small-business owners, because it's due even when no income tax is owed. This calculator estimates it for 2026.
How to use the calculator
- Net self-employment profit. Your business income minus business expenses for the year. For most sole proprietors, that is the profit on Schedule C. Use your best estimate if the year isn't over.
- W-2 wages. Wages from any job where Social Security tax was withheld. These count toward the yearly Social Security cap, so they can lower your SE tax if your total income is high.
- Tax year. The calculator uses the Social Security wage base for the year you choose.
You'll see the Social Security part, the Medicare part, total SE tax, the deduction for half of it, and a quarterly amount with due dates.
How the math works
- Find your SE base. Multiply net profit by 92.35%. This mirrors how an employee's wages exclude the employer's share of the tax.
- Social Security part (12.4%). Apply 12.4% to the SE base, but only up to the yearly cap minus your W-2 wages. The cap, called the Social Security wage base, is $176,100 for 2025 and $184,500 for 2026, according to the 2025 Schedule SE instructions and the 2026 Form 1040-ES.
- Medicare part (2.9%). Apply 2.9% to the whole SE base. There is no cap.
- Total SE tax. Add the two parts.
- Deduction. You can deduct half of your SE tax when figuring adjusted gross income. This lowers your income tax, not your SE tax.
- Quarterly amount. Divide the SE tax by four.
Additional Medicare Tax. A separate 0.9% Additional Medicare Tax applies to wages and self-employment income above $200,000 for single filers, heads of household and qualifying surviving spouses, $250,000 for married couples filing jointly, and $125,000 for married filing separately. These thresholds are set by law and are not adjusted for inflation. The calculator flags when you may be over the line. You figure the tax itself on Form 8959.
Worked example (the default inputs)
Situation: Tax year 2026, net self-employment profit of $60,000, no W-2 wages.
- SE base: $60,000 × 92.35% = $55,410
- Social Security: $55,410 is under the $184,500 cap, so $55,410 × 12.4% = $6,870.84
- Medicare: $55,410 × 2.9% = $1,606.89
- Total SE tax: $8,477.73
- Deduction for half of SE tax: about $4,238.87
- Quarterly share of SE tax: about $2,119.43 per payment
That quarterly figure covers SE tax only. Your estimated payments also need to cover federal income tax on your profit (after the SE tax deduction and your standard or itemized deductions). The 2026 Form 1040-ES worksheet walks through the full estimate.
2026 estimated tax due dates
| Payment | Covers income earned | Due date |
|---|---|---|
| 1st | January 1 – March 31, 2026 | April 15, 2026 |
| 2nd | April 1 – May 31, 2026 | June 15, 2026 |
| 3rd | June 1 – August 31, 2026 | September 15, 2026 |
| 4th | September 1 – December 31, 2026 | January 15, 2027 |
According to Form 1040-ES (2026), you can skip the January 15, 2027 payment if you file your 2026 return by February 1, 2027 and pay the full balance with it. If at least two-thirds of your income is from farming or fishing, different dates apply. You can pay through IRS Direct Pay, your IRS Online Account, or the Electronic Federal Tax Payment System (EFTPS).
If you missed earlier 2026 payments, pay as soon as you can. The underpayment penalty is figured on how late each payment was, so paying now limits it. See the tax calendar for other dates.
Limitations
- Simplified inputs. The tool does not handle church employee income, farm optional methods, the nonfarm optional method, or Conservation Reserve Program payments. Schedule SE covers those.
- Under $400. If your net earnings from self-employment are less than $400, you generally don't owe SE tax. The calculator still shows the math, so check this first.
- Losses and multiple businesses. Combine the net results of all your businesses before entering a figure.
- Couples. Each spouse figures SE tax separately on their own business income, even on a joint return.
- Income tax not included. This is not a full tax estimate.
Related help
If you get a notice about estimated payments, see CP23 or CP2000 if income you received was reported on a Form 1099 but missing from your return. Our hubs for gig workers and freelancers and the self-employed explain record-keeping, and the penalty and interest calculator can estimate costs on a balance you can't pay on time.
Frequently asked questions
Do I owe self-employment tax if I also have a full-time job?
Yes, on your side income, if your net self-employment earnings are $400 or more. Your W-2 wages matter only for the Social Security cap. If wages plus SE income pass the cap, you stop owing the 12.4% part above it.
Is self-employment tax the same as income tax?
No. SE tax funds Social Security and Medicare. Income tax is figured separately using tax brackets. Many self-employed people owe both, and some owe SE tax even when their income tax is zero.
Why only 92.35% of my profit?
It gives you the same treatment as employees, whose employer's half of the tax isn't counted as wages. It equals 100% minus half of the 15.3% rate.
Do retirees who freelance still pay it?
Yes. The IRS says the self-employment tax rules apply no matter how old you are, even if you already receive Social Security or Medicare.
Sources
- Internal Revenue Service (IRS), "Self-employment tax (Social Security and Medicare taxes)". irs.gov
- Internal Revenue Service (IRS), Form 1040-ES (2026), "Estimated Tax for Individuals". irs.gov
- Internal Revenue Service (IRS), 2025 Instructions for Schedule SE (Form 1040). irs.gov
- Internal Revenue Service (IRS), "Estimated tax" FAQs. irs.gov
IRSV.com is an independent guide and is not affiliated with the IRS. This page is general information, not tax or legal advice. Rules change; confirm details on IRS.gov or with a tax professional. Found an error? Tell us.