Quarterly Estimated Tax Calculator (2026)

Self-employed individuals, business owners and anyone with income that has no tax withheld generally pay estimated tax when they expect to owe $1,000 or more for the year.

Paying at least 90% of this year's tax, or 100% of last year's tax (110% if your AGI was over $150,000), through withholding and on-time payments generally avoids the underpayment penalty.

California estimates follow a 30%, 40%, 0% and 30% schedule, so June carries the largest payment and nothing is due in September. Above $1 million of AGI, the prior-year safe harbor doesn't apply.

Federal payments for 2026 are due April 15, June 15 and September 15, 2026, and January 15, 2027. They can be paid through IRS Direct Pay or your IRS online account.

On top of income tax, self-employed individuals pay 15.3% Social Security and Medicare tax on 92.35% of net profit. The Social Security portion stops at $184,500 of earnings for 2026.

Income that comes in unevenly can be handled with the annualized income method, which can lower earlier payments. Estimates are worth revisiting after any big change in income during the year.