If you are self-employed, own an S corporation or have income without withholding, the IRS expects you to pay tax during the year in four installments. Pay enough by each due date and you avoid the underpayment penalty, even if you owe more when you file.
Free tool
Quarterly estimated tax calculator
Work out the federal estimated tax payments that keep you inside the IRS safe harbor, so you avoid an underpayment penalty.
Federal only; special rules apply to farmers and fishermen. Your state may also require estimated payments. Results are estimates for general information only, not legal, tax or financial advice. Confirm them with your own CPA, tax adviser or attorney before making decisions. Using this tool does not create a client relationship with Catching Numbers Inc.
How the safe harbor works
You avoid the federal underpayment penalty if your withholding and estimated payments add up to the smaller of:
- 90% of the tax on this year’s return, or
- 100% of the tax on last year’s return, or 110% if last year’s adjusted gross income was over $150,000 ($75,000 if married filing separately).
Using last year’s tax is the most predictable option, because you know the number on day one. You also owe no penalty if the balance due after withholding is under $1,000.
Quarterly due dates
- 2026 tax year: April 15, June 15 and September 15, 2026, and January 15, 2027
- 2027 tax year: April 15, June 15 and September 15, 2027, and January 18, 2028
Payments can be made through IRS Direct Pay or your IRS online account. Your state may have its own estimated tax rules and dates.
Frequently asked questions
Who has to pay estimated taxes?
Generally anyone who expects to owe $1,000 or more when they file after subtracting withholding and credits: sole proprietors, partners, S corporation shareholders with profit above their salary, and people with investment or rental income.
Can I pay more through withholding instead?
Yes. Withholding counts as if it were paid evenly through the year, so S corporation owners often increase withholding on their salary late in the year to catch up.
Do you prepare tax returns?
No. We keep your books tax-ready all year, so you and your tax CPA can set accurate estimates, and we hand your CPA a complete year-end package.
Know your profit before the estimate is due
Monthly books closed on time mean your quarterly estimates are based on real numbers, not guesses.