Calculate your quarterly estimated tax payments as a self-employed worker in California. Includes self-employment tax (15.3%), federal income tax, and California state income tax. 2026 tax year.
Estimates based on 2025 tax year (2026 filing) brackets. Consult a tax professional for your specific situation.
California has the highest state income tax in the country, with rates up to 12.3% (plus 1% mental health surtax on income over $1M). Self-employed Californians face both federal SE tax and California's steep income tax. Quarterly estimated payments are required if you expect to owe $500+ in state tax.
| Tax Component | Rate / Detail |
|---|---|
| Self-Employment (SE) Tax | 15.3% on 92.35% of net profit |
| Social Security portion | 12.4% (on first $168,600 of net earnings) |
| Medicare portion | 2.9% (no income cap) |
| SE Tax Deduction | Deduct half SE tax from gross income |
| Federal Standard Deduction (Single) | $15,000 (2025 tax year) |
| California State Income Tax | Progressive 1.0%–12.30% |
| Quarterly Due Dates | California quarterly estimated taxes are due April 15, June 15, September 15, and January 15. Required if you expect to owe $500+ in state tax. California also charges an SDI (State Disability Insurance) on self-employment income. |
| Example: $60K Net Profit (Single) | ~$3,685/quarter estimated |
You must pay quarterly estimated taxes if you expect to owe at least $1,000 in federal tax for the year (after withholding and credits). This includes: freelancers, independent contractors, sole proprietors, LLC members, partners, and S-corp shareholders who take distributions. Employees with a side business earning $400+ in net SE income should also pay quarterly on that income.
California quarterly estimated taxes are due April 15, June 15, September 15, and January 15. Required if you expect to owe $500+ in state tax. California also charges an SDI (State Disability Insurance) on self-employment income.
The SE tax rate is 15.3% — 12.4% Social Security plus 2.9% Medicare. It's calculated on 92.35% of your net self-employment income (the 7.65% reduction accounts for the employer-side deduction). For income above $168,600, only the 2.9% Medicare rate applies (no Social Security cap). An additional 0.9% Medicare surtax applies above $200,000 (single) or $250,000 (MFJ).
To avoid the IRS underpayment penalty (currently 8% APR), pay whichever is less: (1) 90% of your current year tax, or (2) 100% of last year's tax (110% if last year AGI was over $150,000). Paying last year's tax amount is the "safe harbor" method — simple and reliable. Most self-employed workers set aside 25-30% of each payment received and pay quarterly.
Federal quarterly taxes: Pay online at IRS.gov/payments (IRS Direct Pay, credit/debit card, or EFTPS). You can also mail Form 1040-ES with a check. California state quarterly taxes: Pay through California's Department of Revenue website. Set up EFTPS for federal payments — it's free and tracks your payment history.