How Much Should You Set Aside for Taxes?

You will owe an underpayment penalty on the shortfall, charged at a variable rate the IRS adjusts quarterly (the federal short-term rate plus 3 points — check IRS.gov for the current period's rate). The penalty accrues from the missed due date until paid, so paying late is always better than not paying at all. Missing one quarter does not lock in penalties for the entire year — catching up the next quarter limits the damage. The IRS Free File and EFTPS systems make it simple to catch up on a missed payment.

To avoid underpayment penalties, pay at least 100% of last year's total tax liability in quarterly installments (or 110% if your prior-year AGI exceeded $150,000). This is the “safe harbor” rule — even if you owe more at filing, you avoid the penalty. For freelancers with unpredictable income, basing quarterly payments on last year's tax is often safer than trying to estimate this year's income precisely. Use the calculator above to estimate your current-year liability, and compare with last year's return to pick the safer path.

They are two separate taxes that stack on top of each other. Self-employment tax (15.3% on net SE income up to the Social Security wage base, then 2.9% above) covers Social Security and Medicare — this is the tax that surprises most new freelancers. Income tax is what W2 employees and self-employed people both owe on taxable income, calculated against the federal brackets (10–37%). As a freelancer, you pay both. The SE tax is particularly impactful because it applies to your full net self-employment income, not just the portion above a standard deduction threshold.

Yes. Quarterly estimated taxes are based on your current-year income, not a fixed annual projection. If your freelance income drops significantly in Q2 or Q3, you can lower your next quarterly payment to reflect the new projection and avoid over-withholding. Use the IRS Annualized Income Installment Method (Form 2210) if your income is highly seasonal — it can reduce or eliminate penalties if income spiked in one quarter and dropped in another.

S-Corp owners who pay themselves a reasonable salary pay FICA taxes (7.65% employee + 7.65% employer match) on that salary, but S-Corp distributions are not subject to self-employment tax. This is the core tax advantage of S-Corp election — splitting income between salary (subject to FICA/SE tax) and distributions (exempt from SE tax) can save thousands. However, the IRS requires the salary to be “reasonable” for your role and industry. See our S-Corp Tax Savings Calculator to model whether election makes sense at your income level.