California Estimated Tax Payments: Due Dates, Safe Harbor, Penalties

California estimated tax payments are quarterly prepayments to the Franchise Tax Board (FTB) that you owe if you expect at least $500 in state tax after withholding and credits ($250 if married or in a registered domestic partnership filing separately). California uses an uneven installment schedule — 30% due April 15, 40% due June 15, nothing in September, and 30% due January 15 — so 70% of the year’s obligation is due by mid-June. Pay enough to hit a safe harbor and you avoid the underpayment penalty, currently calculated at a 7% annual rate.

Who Has to Pay

Two conditions have to both be true. You expect to owe $500 or more in California tax for the year after subtracting withholding and credits ($250 if married/RDP filing separately), and you expect withholding and credits alone to fall short of the safe harbor.¹

The income that typically triggers this: freelance or independent contractor pay, rental income, capital gains from selling investments or property, alimony received, and interest or dividends. Wages generally take care of themselves through employer withholding. Estimated payments fill the gap when no one is withholding on your behalf.

Due Dates and the 30/40/0/30 Split

California does not split the year into equal quarters. Your required annual amount is spread across four periods this way:

First installment, 30%: due April 15
Second installment, 40%: due June 15
Third installment, 0%: nothing due September 15
Fourth installment, 30%: due January 15 of the following year

The zero-percent third installment catches people who are used to the federal system’s even 25% per quarter.² The dates line up with the federal ones, but the amounts don’t, so keep two separate calculations if you owe both. If a due date lands on a weekend or state holiday, the deadline moves to the next business day.

How Much You Need to Pay

The FTB’s Form 540-ES worksheet walks you through projecting your annual income and figuring the installment amounts. What counts as “enough” depends on your income.

The Standard Safe Harbor

For most people, combined withholding and estimated payments have to reach the smaller of two figures: 90% of the current year’s tax or 100% of the tax on last year’s return, including any alternative minimum tax. Meeting either one blocks the penalty even if your final bill turns out higher.²

Higher-Income Rule

If your prior year’s California adjusted gross income was over $150,000 ($75,000 if married/RDP filing separately), the prior-year cushion tightens from 100% to 110%. Your required payment becomes the smaller of 90% of this year’s tax or 110% of last year’s.²

The Millionaire Rule

If your current-year California AGI is $1,000,000 or more ($500,000 if married/RDP filing separately), the prior-year safe harbor disappears. You have to base your payments on 90% of the current year’s tax with no fallback. Copying last year’s payments won’t protect you.² Someone who sells appreciated property, exits a business, or has an unusually large gain can hit this threshold for the first time and need to estimate in real time.

How to Send the Payments

Web Pay

The FTB’s Web Pay portal is free and lets you schedule payments up to a year in advance, through a MyFTB account or as a guest. Scheduling ahead is the simplest way to keep the January installment from slipping past you.³

Credit Card

ACI Payments processes card payments for the FTB and charges a 2.3% service fee. On a $10,000 installment, that’s $230 in fees. Worth it only if the rewards or float justify the cost.⁴

Mail

You can still mail a check or money order with the voucher from Form 540-ES. Make it payable to “Franchise Tax Board,” write your Social Security number or ITIN and the tax year on the check, and send it with the matching quarterly voucher to Franchise Tax Board, PO Box 942867, Sacramento, CA 94267-0008.⁵

When Electronic Payment Becomes Mandatory

Once you make any single estimated or extension payment over $20,000, or file an original return with total tax liability over $80,000, you’re permanently required to pay electronically after that. Every later payment has to be electronic, regardless of amount or tax year. The payment that triggers the rule doesn’t itself have to be electronic, but every one after it does. Paying by paper after that point costs 1% of the payment as a penalty.⁶

What Happens If You Underpay

When your combined withholding and estimated payments fall short by any installment date, the FTB charges a penalty that works like interest: the shortfall multiplied by the number of days it went unpaid, at the FTB’s estimate penalty rate. From July 1, 2025 through June 30, 2026, that rate is 7% per year.⁷

Each installment period is calculated separately, so catching up sooner reduces the total. In most cases the FTB does the math and bills you after your return is filed. If you used the annualized income method, you fill out Form FTB 5805 yourself and attach it to your return.⁸

When the Penalty Doesn’t Apply

No penalty is imposed if the tax owed for the year, after withholding and credits, comes in under $500 ($250 if married/RDP filing separately). That’s the same threshold that decides whether you owed estimated payments in the first place.⁹

Waivers

The FTB can waive the underpayment penalty in narrow situations. A casualty, disaster, or other unusual event may qualify if imposing the penalty would be inequitable. A waiver is also available if you retired after age 62 or became disabled during the tax year or the year before, and the underpayment was due to reasonable cause rather than neglect. Request one by checking “Yes” on Part I, Question 1 of Form FTB 5805, explaining what happened, and attaching the form to your return with supporting documentation.⁸

If Your Income Is Uneven

The 30/40/0/30 default assumes income arrives on a predictable pace. If yours doesn’t, the annualized income installment method lets you calculate each installment based on income actually received through that date rather than a share of the projected annual total.⁸ Seasonal businesses, commission-heavy work, and late-year capital gains are the common reasons to use it. One condition: if you use the annualized method for any installment period, you have to use it for all four.

Applying Last Year’s Refund to This Year

When you file and end up with an overpayment, you can direct some or all of it to next year’s estimated tax instead of taking a refund. Applying a 2025 overpayment, for instance, credits it against the first 2026 installment. Reduce the amount you compute on the 540-ES worksheet by whatever you’ve already applied so you don’t pay twice.³ You can still adjust later installments downward if your outlook changes, as long as you land at or above a safe harbor by year-end.

Disaster Postponements

After a major disaster, the FTB can postpone estimated tax deadlines for affected areas. Following the Los Angeles County fires that began in January 2025, for example, the FTB extended all quarterly estimated tax deadlines for LA County taxpayers to October 15, 2025.¹⁰ Relief usually applies automatically if your principal residence or business sits inside the designated area. Taxpayers outside the zone whose records are inside it can also qualify but generally need to contact the FTB. If you get a penalty notice for a payment that fell inside a postponement window, call the number on the notice to have it reversed.

1
Franchise Tax Board. 2026 Instructions for Form 540-ES Estimated Tax for Individuals
2
Franchise Tax Board. Estimated Tax Payments
3
Franchise Tax Board. 2025 Instructions for Form 540-ES Estimated Tax for Individuals
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Franchise Tax Board. Pay by Credit Card
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Franchise Tax Board. Mailing Addresses
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Franchise Tax Board. Mandatory e-Pay for Individuals
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Franchise Tax Board. Interest and Estimate Penalty Rates
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Franchise Tax Board. 2024 Instructions for Form FTB 5805
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California Legislative Information. California Revenue and Taxation Code 19136
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Franchise Tax Board. Los Angeles County Fires