Side hustle income is taxable even when you have a full-time job. The profit goes on Schedule C, you pay 15.3% self-employment tax on it once it reaches $400, and income tax at your top bracket, because it sits on top of your salary. You can pay through the year with quarterly estimates, or more simply by having your employer withhold extra from your paycheck.

What you owe

  • Income tax on the side profit, at the same brackets as your wages.
  • Self-employment tax of 15.3% on 92.35% of the profit, once it’s $400 or more for the year. If your wages are already above the 2026 Social Security wage base of $184,500, only the 2.9% Medicare part applies.
  • State tax, in most states.

There’s no minimum below which side income is tax-free, and no form has to arrive for it to count. A 1099-K or 1099-NEC only reports what you already owe on.

Why it’s taxed at your top rate

Your salary fills the lower brackets first. Side profit is added on top, so it’s taxed at your marginal rate: 12%, 22% or 24% for most people with a full-time job, before self-employment tax. That’s why the share to set aside from side income is higher than the average rate on your paycheck.

A worked example

A single filer earns $70,000 in salary and makes $10,000 of profit from weekend photography. The side profit is taxed in the 22% bracket, about $1,640 of income tax after the QBI deduction and half the SE tax, plus $1,413 of self-employment tax: roughly $3,050, or 30% of the profit, before any state tax. Without planning, all of it arrives as one bill in April.

Paying it: W-4 or quarterly

Nobody withholds from side income, so the IRS expects payment through the year. Two ways:

  • More withholding at your job. Give your employer a new Form W-4 with an extra amount per paycheck on line 4(c). Withholding counts as paid evenly through the year, even if you start in October, which also helps avoid the underpayment penalty.
  • Quarterly estimated payments on April 15, June 15, September 15 and January 15, if your side income is lumpy or large. See quarterly estimated taxes.

Deductions that count

Costs of the side business come off before any tax: equipment, software, supplies, platform fees, business mileage, and the business share of your phone. Your commute to the day job doesn’t count. If the activity isn’t run to make a profit, it may be a hobby, and then nothing is deductible: see hobby or business. The 1099 tax calculator estimates the tax on your side income.

Questions, answered

Do I have to pay taxes on side hustle income?

Yes. Side income is taxable from the first dollar, and self-employment tax applies once your side profit for the year reaches $400.

How much should I set aside from my side hustle?

Often 25% to 35% of side profit: your top income tax bracket plus 15.3% self-employment tax, plus state tax.

Can I pay side hustle taxes through my W-2 job?

Yes. Submit a new Form W-4 asking for extra withholding on line 4(c). Withholding is treated as paid evenly through the year, so it can replace quarterly estimated payments.

Is there a minimum amount of side income before I pay tax?

No minimum for income tax. Self-employment tax starts at $400 of net profit.

Sources

  1. Manage taxes for your gig work — IRS. Side income is taxable; paying through withholding or estimates.
  2. About Form W-4 — IRS. Extra withholding on line 4(c).
  3. Self-employment tax — IRS. The $400 threshold and the 15.3% rate.
  4. Topic no. 306, Penalty for underpayment of estimated tax — IRS. How withholding counts toward the safe harbor.