Side Hustle Tax Estimator (1099)

Self-employment tax and federal estimate on 1099 income

On $42,000 in gross 1099 income with $8,000 in deductible expenses, net profit is $34,000. Self-employment tax is calculated on 92.35% of that profit at the combined 15.3% Social Security and Medicare rate, coming to $4,804.05. At an estimated 12% federal rate applied after deducting half the SE tax, the federal estimate is $3,791.76. After both, you'd keep $25,404.20 of the original $42,000.

That's a combined effective rate of about 25.2% on gross income, and self-employment tax alone -- the 15.3% payroll tax a W-2 employee would split with an employer -- accounts for roughly half of the total tax bill in this example.

Expenses matter twice here: they reduce profit directly, which reduces both the SE tax base and the federal taxable amount. An extra $1,000 in legitimate deductions saves roughly $267 in this example (15.3% SE savings plus a slice of federal tax on the SE deduction).

What this estimate simplifies

SE tax uses 92.35% of profit and 15.3%. Federal band is a flat planning rate, not a filing. Real federal tax uses marginal brackets, not one flat rate, and doesn't account for the standard deduction, other income, or credits -- so the $3,791.76 federal figure is a rough planning number, not what you'll actually owe.

State income tax isn't modeled at all. If you're in a state with income tax, add that on top of the federal estimate before deciding how much to set aside.

For a rate that already builds in taxes and business costs so you're not solving this after the fact, the Freelance Rate Calculator works backward from a target take-home instead.

Structuring around this tax bill

Once 1099 profit reaches a level where the 15.3% SE tax becomes a meaningful cost, some people evaluate an S-corp election specifically to reduce it -- the S-Corp Tax Savings Calculator models that trade-off.

An HSA contribution is one of the few moves that reduces both the federal estimate and, depending on your setup, self-employment income -- see the HSA Contribution Tax Savings Calculator.

Frequently Asked Questions (FAQ)