Quarterly Estimated Tax Calculator
Enter your income quarter-by-quarter. Uses the IRS Form 2210 annualized income installment method — so each payment reflects what you actually earned, not a flat 25% of a guessed annual total.
Enter your quarterly income and click Calculate to see each estimated tax payment.
Uses IRS Form 2210 Schedule AI — the annualized income installment method.
What are quarterly estimated taxes and how are they calculated for freelancers?
Quarterly estimated taxes are advance payments of income and self-employment tax that self-employed individuals must make four times per year to avoid IRS underpayment penalties. Unlike employees, freelancers have no employer withholding taxes from each paycheck — so the IRS requires them to pay as income is earned, not just at year-end. The IRS-preferred method for freelancers with irregular income is the annualized income installment method (Form 2210, Schedule AI), which calculates each payment based on income actually earned through that period rather than assuming equal income each quarter. Self-employment tax (15.3% on 92.35% of net SE income) is calculated separately and added to income tax to determine the total quarterly obligation. Sources: IRS Publication 505; IRS Form 2210.
Why "divide by 4" is wrong for freelancers
Most freelance income is lumpy — a big project in Q1, a slow Q2, a surge in Q3. If you simply estimate your annual income and pay 25% per quarter, you'll either overpay early (lending money to the IRS interest-free) or underpay later (triggering underpayment penalties).
The IRS offers a better method: the annualized income installment method (Form 2210, Schedule AI). Instead of dividing a guess about your full year, you annualize what you've actually earned through each period, calculate the tax on that, and apply cumulative percentages.
Safe harbor alternative: If you prefer simplicity, you can avoid underpayment penalties by paying 100% of last year's tax liability (110% if last year's AGI exceeded $150,000). Divide your prior-year tax bill by 4 and pay that each quarter — but you may still owe a lump sum at filing.
What this calculator does not account for: tax credits (Child Tax Credit, education credits, etc.), additional Medicare tax on high earners, state-specific rules beyond a flat rate, or the prior-year safe harbor. For anything beyond straightforward freelance income, work with a CPA.
Use your marginal rate or last year's effective rate from your state return. These are 2025 top marginal rates for reference — not your rate.
Frequently asked questions
How much should I set aside for taxes as a self-employed freelancer?
A practical rule of thumb is 25–30% of net self-employment income for federal taxes. This covers self-employment tax (15.3% on 92.35% of net income) plus federal income tax after deductions. Freelancers in high-tax states (California, New York, Oregon) or higher income brackets should set aside 35–40%. The 30% rule overpays slightly for most freelancers — this calculator gives you a precise figure so you don't leave money idle unnecessarily.
What is self-employment (SE) tax and how is it calculated?
Self-employment tax is the freelancer's version of FICA (Social Security + Medicare). Employees split this 15.3% with their employer; you pay the full amount yourself. The calculation has two parts: Social Security (12.4%, applied up to the $176,100 wage base for 2025) and Medicare (2.9%, no cap). SE tax applies to 92.35% of net SE income — not 100% — because the other 7.65% represents the employer's share that would have been excluded from a W-2 employee's wages. You can then deduct half of the SE tax above the line on your 1040, reducing federal taxable income. Source: IRS Pub. 505.
What happens if I miss or underpay a quarterly estimated tax payment?
The IRS charges an underpayment penalty equal to the federal short-term rate plus 3 percentage points (currently ~7–8% annualized) on each quarter's shortfall. The penalty is calculated separately per quarter — paying extra in Q4 does not retroactively fix a Q2 underpayment. You avoid the penalty by paying at least 90% of the current year's liability using the annualized installment method (Form 2210), or 100% of last year's tax (110% if prior-year AGI exceeded $150,000).
What is the QBI deduction and does it apply to freelancers?
The 20% Qualified Business Income (QBI) deduction under IRC §199A allows most self-employed individuals to deduct up to 20% of net business income from federal taxable income — reducing the income tax (but not SE tax) on that amount. For 2025, the full deduction is available to single filers with taxable income below $197,300 (MFJ: $394,600). Above those thresholds, the deduction phases out for "specified service trade or business" owners (lawyers, consultants, financial advisors, health professionals, etc.). Freelancers in creative, tech, or trade fields often qualify even at higher incomes. This calculator includes a QBI toggle — check it if you believe you qualify and use the result as a planning estimate only; confirm with a CPA.