Self-Employment Tax Guide 2026: How Much 1099 & Freelance Income Owes the IRS

Every dollar of 1099, freelance, or small-business net profit carries two separate tax obligations: self-employment tax (the self-employed version of FICA) and ordinary federal income tax. Freelancers new to self-employment are often blindsided by the first one, since no employer is withholding it — and the calculator on this page is built to show both together, exactly the way they'll actually hit your bank account.

Worked example: $90,000 in gross revenue, $20,000 in business expenses, $5,000 in other deductions, filing single. Net profit is $65,000. Net SE earnings after the 92.35% factor are $60,027.50. Social Security tax is $7,443.41 (12.4%), Medicare tax is $1,740.80 (2.9%), for total SE tax of $9,184.21. Half of that — $4,592.10 — is deductible, bringing federal taxable income down to $44,307.90 after the standard deduction. Federal income tax on that comes to $5,068.95. Total tax liability: $14,253.16, or 21.93% of net profit.

The phrase "self-employment tax with deductions" usually means one of two different things, and it's worth separating them because they affect your tax bill in different ways:

• Business deductions (home office, mileage, equipment, Section 179, supplies, software) reduce your net profit — the number SE tax is calculated on. Every dollar of legitimate business deduction lowers both your SE tax and your income tax.
• The SE tax deduction itself (half of your SE tax, claimed on Schedule 1) only reduces your federal income tax base. It does not reduce the SE tax calculation — that would be circular, since you'd need the SE tax figure to calculate the deduction that reduces the SE tax figure.

A common category worth flagging separately: SEP-IRA and Solo 401(k) contributions. These are powerful — a self-employed person can often shelter 20% or more of net profit — but they reduce federal taxable income, not the SE tax base. Contributing $10,000 to a Solo 401(k) won't lower your Social Security or Medicare tax by a cent, but it will lower your federal income tax bracket exposure. The calculator's federal estimate section lets you enter a retirement contribution amount to see that effect isolated.

"Self-employment tax calculator federal" searches are usually looking for one combined number: total tax owed, self-employment and income tax together, not two separate calculators to add up by hand. That's the exact gap this tool fills — turn on "Include Federal Income Tax Estimate" and it runs your net profit through the same 2026 IRS bracket logic as the site's Federal Tax Bracket Calculator, after subtracting the SE tax deduction, any retirement contribution, and your filing status's standard deduction.

One nuance that trips people up: the federal estimate here assumes the standard deduction, since that's the right default for most freelancers and the majority of the searches this page targets. If you itemize — large mortgage interest, charitable giving, high state and local taxes — your actual federal tax will differ from the estimate. Use this tool for planning and quarterly-payment sizing, and confirm the final number with a tax professional or software like TurboTax or H&R Block at filing time, especially in your first year or two of self-employment when the numbers are least predictable.

Because no employer withholds tax from 1099 or freelance income, the IRS expects you to send it in yourself, four times a year, through estimated payments. Skip this and you can owe an underpayment penalty even if you pay everything correctly by April 15 the following year — the penalty is based on when you paid, not just how much.

The rule that determines how much to pay is the safe-harbor rule: pay in the smaller of 90% of this year's projected tax, or 100% of last year's tax (110% if your prior-year AGI was over $150,000). Whichever is smaller is your legal minimum to avoid a penalty — and for someone with growing income, last year's number is usually the easier, lower target to hit.

Due dates are April 15, June 15, September 15, and January 15 of the following year — not evenly spaced, since Q2 covers only two months (April and May). Run the numbers in the Quarterly Estimated Tax Calculator, which applies this exact rule to your projected income and prior-year tax.

A handful of mistakes show up repeatedly in the first year or two of self-employment:

• Confusing gross revenue with taxable profit. Someone billing $90,000 for the year doesn't owe tax on $90,000 — only on profit after legitimate business expenses.
• Forgetting SE tax exists at all. Employees see FICA disappear from every paycheck automatically. The self-employed owe the same tax but have to calculate and pay it themselves — it's easy to budget only for income tax and get a nasty surprise.
• Paying quarterly taxes based on gut feel instead of the safe-harbor formula. Underpaying triggers a penalty; wildly overpaying just means an interest-free loan to the government you didn't need to make.
• Not tracking W-2 wages against the Social Security wage base when self-employment is a side income alongside a full-time job — this can lead to overpaying Social Security tax on the self-employment side if it's calculated in isolation.
• Skipping retirement contributions because the SE tax bill already feels large — a SEP-IRA or Solo 401(k) contribution doesn't touch SE tax, but it's one of the few remaining levers to meaningfully lower the federal income tax portion.