Contractor Tax Calculator

Find out what to set aside for taxes. Enter your Schedule C net profit and filing status to see your self-employment tax, federal income tax, §199A deduction, and the quarterly estimated payment that keeps you out of underpayment penalties, using published IRS figures for the 2026 tax year. Federal only, free, no signup.

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Contractor Tax Calculator

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Tax year 202622.0% marginal bracket

Estimated payment per quarter

$5,032

Set aside 22.4% of every profit dollar · $22,364 total federal tax

Safe harbor: 90% of this year’s tax
Self-employment tax15.3% on $92,350 of net earnings
$14,129

Estimate for planning, not tax advice. Federal only — state and local income tax are not modelled, and many states and cities also require their own quarterly estimated payments. Consult a CPA or enrolled agent before you file or change what you pay in.

Your federal tax at a glance
Total federal tax
$22,364Income tax + self-employment tax + Additional Medicare
Net earnings from SE
$92,350Schedule C net profit × 92.35%
Social Security (12.4%)
$11,451On $92,350 — capped at the wage base
Medicare (2.9%)
$2,678Uncapped — applies to every dollar of net earnings
Half of SE tax deducted
−$7,065Above-the-line adjustment on Schedule 1
Adjusted gross income
$92,936All income less half of SE tax and your above-the-line deductions
Standard deduction
−$16,100Itemized deductions are not modelled
QBI (§199A) deduction
−$15,36720% of qualified business income, under the threshold
Taxable income
$61,468Income tax on this: $8,235
Effective rate on profit
22.4%Total federal tax ÷ Schedule C net profit
Q1 — April 15, 2026
$5,032Pay via IRS Direct Pay or EFTPS
Q2 — June 15, 2026
$5,032
Q3 — September 15, 2026
$5,032
Q4 — January 15, 2027
$5,032

Payments are split evenly across four periods. If your income is lumpy, the annualized income installment method (Form 2210 Schedule AI) can lower the early-quarter payments — that method is not modelled here.

Required for the year
$20,12890% of this year’s estimated tax
Already paid in
$0Withholding plus estimated payments you have already made
Still owed at filing
$2,236If you pay only the safe harbor — it avoids the penalty, not the tax
Pay the full estimate instead
$5,591Per quarter to owe nothing at filing

You avoid the underpayment penalty by paying the smaller of 90% of this year’s tax or 100% of last year’s (110% if last year’s AGI was over the threshold). No penalty applies at all if the balance due is under $1,000.

  • Social Security (12.4%): $11,451
  • Medicare (2.9%): $2,678
  • Federal income tax: $8,235

$22,364 total · $14,129 of it is self-employment tax you would not owe as a W-2 employee paying only half.

Social Security wage base
$184,500
SE tax rate
15.3% on 92.35% of net profit
Additional Medicare threshold
$200,000
Standard deduction
$16,100
QBI (§199A) threshold
$201,750
Prior-year safe harbor
100% (110% over $150,000 AGI)

Sources: Rev. Proc. 2025-32 (2026 figures) · Schedule SE instructions · Form 8959 (Additional Medicare) · Form 8995-A (QBI) · Pub 505 (estimated tax) · Form 2210 (safe harbor)

  • State and local income tax — not modelled at all. Most states tax this income too, and many require their own quarterly estimated payments on their own schedule.
  • S-corporation reasonable-salary treatment. This models a sole proprietor or single-member LLC filing Schedule C. An S-corp election splits profit into wages and distributions and changes the self-employment tax entirely.
  • Capital gains, qualified dividends, and the Net Investment Income Tax. Anything you enter as other income is taxed at ordinary rates.
  • Itemized deductions, tax credits (child tax credit, energy credits, premium tax credit), AMT, and the additional standard deduction for age 65+ or blindness.
  • The annualized income installment method (Form 2210 Schedule AI), which can lower early-quarter payments when your income is seasonal.
  • Multiple businesses, partnership or S-corp K-1 income, REIT dividends, and PTP income in the §199A calculation.
  • Assumption: the new §199A minimum deduction ($400 for 2026 when you have at least $1,000 of qualified business income) is treated as a floor that the overall 20%-of-taxable-income limit still caps, and material participation is assumed.

  • Enter your net business profit

    Your Schedule C bottom line for the year: revenue minus every deductible business expense. Add any W-2 wages you also earn, since your own wages use up the Social Security wage base before your business profit does.

  • See the full federal picture

    Self-employment tax at 15.3% on 92.35% of net earnings, the Social Security cap, Additional Medicare above the threshold, the deductible half of SE tax, the standard deduction, the 20% QBI deduction, and income tax at your bracket.

  • Get your quarterly payment and safe harbor

    The calculator shows what to send in on each of the four due dates, and whether 90% of this year or 100%/110% of last year is the cheaper way to stay penalty-free.

How it works

  1. 1

    Enter your net business profit

    Your Schedule C bottom line for the year: revenue minus every deductible business expense. Add any W-2 wages you also earn, since your own wages use up the Social Security wage base before your business profit does.

  2. 2

    See the full federal picture

    Self-employment tax at 15.3% on 92.35% of net earnings, the Social Security cap, Additional Medicare above the threshold, the deductible half of SE tax, the standard deduction, the 20% QBI deduction, and income tax at your bracket.

  3. 3

    Get your quarterly payment and safe harbor

    The calculator shows what to send in on each of the four due dates, and whether 90% of this year or 100%/110% of last year is the cheaper way to stay penalty-free.

How contractor contractors estimate quarterly taxes

Nobody withholds tax from a Schedule C profit. You owe self-employment tax, 15.3% on 92.35% of net earnings, covering both halves of Social Security and Medicare, on top of ordinary income tax, and the IRS wants it four times a year, not once in April. A contractor owner clearing $120,000 in profit is looking at roughly $17,000 of SE tax before a dollar of income tax, which is why "set aside 25–30% of profit" is the rule of thumb every bookkeeper repeats.

This calculator walks the actual return: Schedule SE for the 15.3%, the Social Security wage base cap, Form 8959 for Additional Medicare, the above-the-line deduction for half your SE tax, the standard deduction, the §199A qualified business income deduction with its threshold and W-2 wage limit, and the graduated brackets. Then it applies the §6654 safe harbor so you know the smallest amount that keeps the underpayment penalty away. Every rate, bracket, and threshold comes from published IRS sources for the tax year shown, and nothing is extrapolated. It is federal only: state and local income tax are not modelled, and this is a planning estimate, not tax advice.

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Contractor Tax Calculator FAQs

How much should a contractor contractor set aside for taxes?

For most owner-operators it lands between 25% and 33% of net profit once self-employment tax and federal income tax are combined, but the real number depends on your filing status, other household income, and whether the QBI deduction applies. Run your own profit through the calculator instead of guessing, and remember to add your state's rate on top, because this tool is federal only.

As an employee, you pay 7.65% of your wages to Social Security and Medicare and your employer pays the matching 7.65%. Self-employed, you are both, so you pay the full 15.3%, applied to 92.35% of your net earnings. The Social Security portion (12.4%) stops at the annual wage base; the Medicare portion (2.9%) never stops. You do get to deduct half of it against your income tax.

Four times a year: April 15, June 15, September 15, and January 15 of the following year, with dates sliding to the next business day when they land on a weekend or holiday. Pay through IRS Direct Pay or EFTPS. Missing a quarter can trigger an underpayment penalty even if you pay in full by April.

You avoid the underpayment penalty by paying in the smaller of 90% of this year’s tax or 100% of last year’s total tax, or 110% if last year’s adjusted gross income was over $150,000 ($75,000 if married filing separately). In a fast-growing year the prior-year route is usually far cheaper. No penalty applies at all if your balance due comes in under $1,000.

Usually yes. The §199A deduction lets pass-through owners deduct up to 20% of qualified business income, and contracting trades are not specified service businesses, so the SSTB restriction does not hit you. Above the taxable-income threshold the deduction gets capped by 50% of the W-2 wages your business pays, which is why a sole proprietor with no payroll can lose most of it at higher incomes.

No. It models federal tax only: self-employment tax, federal income tax, Additional Medicare, and the QBI deduction. Most states tax this income too and many require their own quarterly estimated payments on their own schedule. It also does not model an S-corp salary split, capital gains, credits, or itemized deductions. Treat the result as a planning estimate and confirm with a CPA or enrolled agent before you file.

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