San Diego County & California

How to pay California estimated taxes

Yachts docked in a San Diego marina with downtown towers and the convention center behind them

How San Diego filers pay the Franchise Tax Board

  • Individuals can pay the Franchise Tax Board (FTB) free through Web Pay, and FTB requires electronic payment after one estimate or extension payment over $20,000 (2026).
  • Filers owe 30% of the 2026 estimate by April 15, another 40% by June 15 and the last 30% by January 15, 2027.
  • FTB charges a 7% annual penalty rate (2026) on late or short installments.

Next step for freelancers: check federal self-employment tax rules on California self-employment tax.

Freelancers and other filers with little or no withholding pay FTB estimated tax, the year's expected California tax minus withholding and credits, in installments.

How to pay California estimated taxes online or by check

FTB takes 2026 estimates by Web Pay, card or check, and only check payers mail a Form 540-ES voucher.

Web Pay
FTB debits a bank account, and filers can schedule a payment up to one year ahead.
Credit card
ACI Payments charges a 2.3% fee.
Check
Filers mail a check to the Franchise Tax Board, marked with their taxpayer ID and “2026 Form 540-ES”, to PO Box 942867, Sacramento, CA 94267-0008.

After an estimate or extension payment over $20,000, or an original return with tax over $80,000, FTB requires electronic payment and charges a 1% penalty on paper payments.

How much California estimated tax to pay

Filers expecting to owe FTB $500 or more for 2026 after withholding and credits ($250 married filing separately) avoid a penalty by paying at least:

  • 90% of 2026 tax or 100% of 2025 tax, whichever is smaller
  • Above $150,000 of 2025 California adjusted gross income (AGI), $75,000 married filing separately: 90% of 2026 tax or 110% of 2025 tax, whichever is smaller
  • From $1,000,000 of 2026 California AGI, $500,000 married filing separately: 90% of 2026 tax only

Sorrento Valley biotech staff with stock income can raise withholding instead, on Employment Development Department Form DE 4.

Red San Diego trolley passing under palm trees with downtown towers behind

California estimated tax due dates for 2026

An Encinitas wedding photographer with no withholding, 2025 California AGI of $95,000 and 2026 AGI under $1,000,000 avoids a penalty by paying 100% of the 2025 tax, $6,000:

April 15, 2026

30%: $1,800

June 15, 2026

40%: $2,400

September 15, 2026

No California payment; filers still owe the IRS a federal estimate

January 15, 2027

30%: $1,800, or nothing if the photographer files the 2026 return and pays in full by January 31, 2027

FTB charges about $14 if the photographer pays the $2,400 June installment 30 days late: $2,400 × 7% × 30 ÷ 365 = $13.81 (Form 5805).

FTB can postpone due dates after a disaster. Following the January 2024 floods, it moved San Diego County's April 15 and June 15, 2024 estimates to June 17, 2024.

Downtown San Diego skyline across the bay with a sailboat on the water

When to hire a CPA for the annualized income method

Ask a certified public accountant (CPA) to test the annualized income method before the April installment; under it, filers base each installment on income earned so far.

Filers who use the method for one due date must use it for all of them. Use how to choose a CPA to compare firms.

Sources:

  • Franchise Tax Board: 2026 Form 540-ES instructions, estimated tax payments, Web Pay, credit card payments, interest and estimate penalty rates, 2025 Form 5805 instructions and San Diego County flood relief
  • Internal Revenue Service: 2026 Form 1040-ES
  • Employment Development Department: Form DE 4