Short version: 25–30% of profit is the range most people land in, and 30% is the safer end to start with. But that number is doing a lot of hidden work, and if you don’t know what’s inside it you can’t tell when it stops applying to you. Here’s the whole thing, worked through.

What should you set aside?

Enter your profit — what’s left after business expenses, not what a client paid you.

Set aside each year $18,000
Per month$1,500
Per quarterly payment$4,500
Yours to spend$42,000

On every $1,000 that lands, hold back $300.

An estimate, not tax advice. It applies one flat percentage to profit — which is exactly how a set-aside rule should work day to day, and exactly what an actual return does not do. Your bracket, filing status, state, deductions and credits all move the real number. Use this to decide what to hold back; use an accountant to decide what to file.

You’re paying two different taxes

This is the part that catches people who’ve only ever had a W-2 job. When you’re self-employed you owe two separate things, and they’re calculated differently:

  1. Self-employment tax — Social Security and Medicare. Flat rate. Starts at almost the first dollar of profit.
  2. Income tax — federal, plus state if your state has one. Progressive, so the rate climbs as you earn more.

An employee pays these too. The difference is that their employer quietly covers half the Social Security and Medicare bill and withholds the rest from every paycheck. Nobody does that for you. You’re both the employer and the employee now, so you pay both halves — and you pay them yourself, on a schedule.

Self-employment tax: the 15.3% you always owe

Self-employment tax is 15.3% — 12.4% for Social Security and 2.9% for Medicare. Two details make the real number lower than 15.3% of your profit:

If your net profit for the year is under $400, you don’t owe self-employment tax.

Income tax: the part that depends on your bracket

This is why nobody can hand you a single correct percentage. Your federal income tax depends on your total taxable income, your filing status, your standard or itemized deduction, and any other income in the household — a spouse’s salary can push your freelance income into a higher bracket even if the freelance income itself is modest.

Then there’s state. Some states take nothing. Others take a meaningful slice. Two people with identical books in different states owe genuinely different amounts.

Why the range is 25–30%

Self-employment tax alone is roughly 14.1% of profit once the 92.35% adjustment is applied. Add a low-to-middle federal bracket and you land in the mid-twenties. Add a state income tax and you’re near or above 30%. That’s the whole derivation — it isn’t a rule of thumb someone invented, it’s just the two taxes added together.

A woman at a kitchen table in the evening, one lamp lit, working through a small stack of papers with a calculator.
The arithmetic is worth doing once, properly, at a kitchen table. It is a smaller job than the dread around it suggests, and the number it produces is the same number every payment for the rest of the year.

Worked example: $60,000 of profit

Say you invoiced $68,000 and had $8,000 of legitimate business expenses, leaving $60,000 of net profit. Single filer, no state income tax, taking the standard deduction.

Self-employment tax

Net profit$60,000
× 92.35% (the adjustment)$55,410
× 15.3%$8,478
Self-employment tax$8,478

That’s about 14.1% of the original $60,000 — the effective rate, before any income tax at all. Half of it is deductible against your income tax, which softens the next step slightly.

Roughly, all in

Self-employment tax~$8,478
Federal income tax (after standard deduction and the half-SE deduction)~$5,000–6,000
Total, approximate~$13,500–14,500

That’s roughly 23% of profit for this particular person. Set aside 25% and you’re covered with a little slack. Set aside 30% and you’ll have a refund or a head start on next year. Add a state income tax and 30% stops being generous and starts being about right.

Percentage of profit, not revenue

Tax is charged on what’s left after expenses. If you set aside 30% of every payment that lands without accounting for your costs, you’ll over-save — which is a nicer problem than the reverse, but it’s still money sitting idle. If your expenses run about 15% of revenue, holding back 25% of each payment gets you close to 30% of profit.

Where $60,000 of profit actually goes

Single filer, standard deduction, no state income tax.

14%$8,4789%$5,50077%$46,022
Self-employment tax Federal income tax Yours to keep
About 23% of profit goes to federal tax for this particular person — which is why 25% is the floor and 30% gives you slack. The income-tax slice is the middle of the $5,000–6,000 range above; your bracket, filing status and state all move it.

Set it aside per payment, not per quarter

The arithmetic above is annual, but the habit that makes it work is per-payment. Every time money lands, move your percentage into a separate account immediately — same day, before it’s mentally spent.

This matters more when income is irregular. If you make most of your year in three good months, a “save at the end of the quarter” plan means the tax on a big March hasn’t been set aside by the time a dead April arrives and you need that cash to live on. Money taken off the top on the day it arrives never enters the pool you budget from.

Quarterly estimated tax payments

The IRS expects payment through the year, not in one lump at filing. For self-employed people that means quarterly estimated payments, due roughly mid-April, mid-June, mid-September, and mid-January of the following year.

Exact dates move when they’d fall on a weekend or a holiday, so check IRS.gov each year rather than trusting a date you remember. Underpaying can bring a penalty even if you settle up in full at filing time.

A man standing in his own driveway on a spring morning with a coffee mug, relaxed, an ordinary house behind him.
This is what setting aside actually buys: April arrives, the bill is what you expected, and the money is already there. Nothing dramatic happens. That is the whole point.

When to stop using a percentage

A flat percentage is a good default and a bad permanent answer. Revisit it if:

The practical move: set aside 30% for one full quarter, then compare it against what you actually owe. You’ll learn your real number faster than any calculator can tell you.

BrassWell does this part automatically

A running tax estimate that updates every time you log income, and a share of everything coming in earmarked before you can spend it.

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Questions, answered

What percentage should I set aside for taxes as a freelancer?

25–30% of net profit is the usual working range for someone in the lower federal brackets with no state income tax. It is a starting point, not an answer — your bracket, your state, and your deductions all move it. Set aside 30% for a quarter, compare it to what you actually owe, and adjust.

What is self-employment tax?

Self-employment tax is Social Security and Medicare for people without an employer. It is 15.3% total — 12.4% Social Security plus 2.9% Medicare — charged on 92.35% of your net profit. For 2026 the Social Security portion applies only up to $184,500 of earnings; the Medicare portion has no cap.

Do I set aside a percentage of revenue or profit?

Profit, not revenue. Tax is charged on what is left after business expenses. Setting aside a percentage of every payment that lands is simpler in practice, but the percentage should be derived from your expected profit margin, or you will over-save.

When are quarterly estimated taxes due?

Roughly mid-April, mid-June, mid-September, and mid-January of the following year. Exact dates shift when they fall on a weekend or holiday, so check IRS.gov each year rather than relying on a remembered date.

Sources

  1. Self-employed individuals tax center — IRS. The $400 net-earnings threshold, and what self-employment tax covers.
  2. Self-employment tax (Social Security and Medicare taxes) — IRS. The 15.3% rate, its 12.4% and 2.9% halves, and the Social Security wage ceiling.
  3. Estimated taxes — IRS. Who has to pay quarterly, and the payment methods.
  4. Publication 505, Tax Withholding and Estimated Tax — IRS. The safe-harbor rules, in full and in the IRS’s own words.
  5. Form 1040-ES, Estimated Tax for Individuals (PDF) — IRS. The worksheet that decides whether you owe quarterly payments at all.

This is general information, not tax advice. BrassWell isn’t a tax preparer and doesn’t file returns. The figures here cover US federal self-employment and income tax at a high level, and deliberately skip filing status differences, itemized deductions, credits, the qualified business income deduction, state and local tax, and plenty else that will apply to you. Rates and thresholds change annually. Talk to a CPA or enrolled agent for numbers you can rely on.