California estimated tax due dates for 2026
California estimated income tax payments for tax year 2026 are due April 15, 2026, June 15, 2026, January 15, 2027 in uneven installments (30% / 40% / 0% / 30% of the required annual payment). That differs from the federal schedule. Below: who has to pay, how to avoid an underpayment penalty and where to pay, with the official source.
| Payment | California due date | Share of annual payment |
|---|---|---|
| 1 | 30% | |
| 2 | 40% | |
| 3 | 30% |
Federal 2026 estimated tax due dates, for comparison: April 15, 2026, June 15, 2026, September 15, 2026, January 15, 2027.
Who must pay California estimated tax?
Generally, you must make estimated tax payments if you expect to owe at least $500 ($250 if married/RDP filing separately) in tax for 2026 (after subtracting withholding and credits) and you expect your withholding and credits to be less than the smaller of: 90% of the tax shown on your 2026 tax return; or 100% of the tax shown on your 2025 tax return including Alternative Minimum Tax (AMT).
How do you avoid a California underpayment penalty?
Lesser of 90% of 2026 tax or 100% of 2025 tax (incl. AMT). If 2025 California AGI > $150,000 ($75,000 MFS/RDP separately), use 110% of 2025 tax instead of 100%. If 2026 California AGI >= $1,000,000 ($500,000 MFS), estimates must be based on 2026 tax (prior-year safe harbor unavailable). Farmers/fishermen: 66 2/3%. Filing the 2026 return by Jan 31, 2027 and paying in full replaces the 4th installment.
How much should you pay?
Start with your federal estimate: the free Quarterly Estimated Tax Calculator works out your 2026 federal payments and safe harbor. California figures its own tax, so the state amount is separate.
