California (CA) Quarterly Estimated Tax Calculator

Yes. California requires estimated tax payments if you expect to owe at least $500 ($250 for married filing separately) in CA income tax for the year. The CA FTB schedule differs from the federal schedule: Q1 (April 15) = 30% of annual estimate; Q2 (June 15) = 40%; no Q3 payment; Q4 (January 15) = 30%. Verify current percentages at ftb.ca.gov. This calculator shows an equal-quarter approximation; adjust your April and June payments upward per the CA FTB schedule.

California's estimated tax installment schedule for 2026 is: April 15 (30% of estimated CA tax), June 15 (40%), no September payment, January 15, 2027 (30%). This differs from the federal 25/25/25/25 split. A freelancer owing $8,000 in CA income tax should pay approximately $2,400 in April, $3,200 in June, nothing in September, and $2,400 in January — not four equal payments of $2,000. Source: California FTB Publication 1005.

California charges an underpayment penalty of approximately 5.7% annualized on any shortfall (Form 5805). The CA safe harbor is 100% of the prior year's CA tax liability or 90% of the current year's liability — whichever is smaller. Paying 100% of last year's CA tax across the 30/40/30 schedule avoids the penalty.

Yes. Freelancers in California who expect to owe more than $500 in state income tax (threshold varies; check with the California Department of Revenue) are generally required to make quarterly estimated state tax payments. These are separate from your federal 1040-ES payments.

Federal estimated tax payments for 2026 are due on: April 15 (Q1), June 16 (Q2, adjusted from June 15), September 15 (Q3), and January 15, 2027 (Q4). Missing a payment or underpaying may result in a penalty under IRS Form 2210, even if you pay in full by April 15.

The calculator estimates your annual tax liability: (1) SE tax on 92.35% of net profit × 15.3%; (2) federal income tax on taxable income (AGI minus standard deduction, minus optional QBI deduction); (3) state income tax using your state's rates and deduction rules. It then subtracts withholding and divides by 4 (federal) or applies the state's installment schedule.

The IRS charges a penalty for underpaying estimated taxes (Form 2210). For 2026, the penalty rate is approximately 7–8%. To avoid the penalty, pay either 90% of this year's tax or 100% of last year's tax (110% if last year's AGI exceeded $150,000). Using the safe harbor based on last year's return is often the simplest approach for freelancers with variable income.

The IRS and most states require quarterly (not monthly) estimated tax payments. However, you can pay more frequently or in advance of due dates — overpaying is not penalized. Many freelancers find it easier to set aside a fixed percentage of each invoice payment and make monthly deposits, then ensure each quarterly deadline's cumulative amount meets the required installment.