Why does California have a different quarterly schedule than the IRS?

California set its own schedule independently of the federal government. The FTB requires a larger payment upfront (Q1 + Q2 combined = 70% of the year's liability) compared to the IRS's even 25% per quarter. The practical effect is that California owners need more cash available in April and June.

What happens if I pay California on the federal schedule (25% each quarter)?

If you pay 25% in April instead of 30%, you're underpaying Q1 by 5% of your annual estimate. The FTB will charge an underpayment penalty on that shortfall even if your total payments for the year are correct. The penalty rate is modest but avoidable.

Is there really no California payment due in September?

Correct. The federal Q3 payment is due September 15 — California has no Q3 payment. Your next California payment after June 15 is January 15 of the following year. Sending a California payment in September is voluntary prepayment, not a required installment.

What are the exact California estimated tax due dates?

Q1: April 15 (30% of annual estimate). Q2: June 15 (40% of annual estimate). Q3: No California payment due. Q4: January 15 of the following year (30% of annual estimate). These dates can shift if they fall on a weekend or holiday.

How does the California safe harbor work for estimated taxes?

If you pay 100% of your prior year California tax liability, distributed according to the CA schedule (30/40/0/30), you avoid underpayment penalties regardless of what you actually owe this year. This is useful when income is hard to predict.

Does the PTET payment change my quarterly estimated tax requirements?

Yes. When an S-corp or partnership makes a PTET prepayment by June 15, that can reduce or eliminate your personal California estimated tax obligation — because the entity is paying California income tax on your behalf at the entity level. The personal California credit from PTET means you may owe nothing personally on that income.

California taxes

California Quarterly Estimated Tax Schedule: Why It's Different from Federal

California's quarterly estimated tax schedule is 30% in April, 40% in June, nothing in September, and 30% in January — not the 25/25/25/25 federal schedule. Using the wrong one means penalties.

Written by Matt Reese, CPA · 5 min read · Published April 2026·Share on LinkedIn

Key Takeaways

California's quarterly schedule is 30% (April), 40% (June), 0% (September), 30% (January) — front-loaded compared to the federal 25/25/25/25.
The September skip is the most commonly missed detail. Many California owners send a payment in September following the federal calendar — the FTB doesn't require it, and it doesn't credit toward your January bill.
If you underpay your Q1 or Q2 California estimate, the FTB charges an underpayment penalty even if you're current with the IRS.
California has an additional complication for new businesses: the $800 LLC fee is also due April 15, on top of the Q1 estimated tax payment.
The safe harbor rule works differently in California: you avoid penalties if you've paid 100% of the prior year's liability, distributed across the CA schedule — not the federal one.

The September non-payment is the most common mistake

Many California business owners send a quarterly payment in September because they’re following the federal schedule. The FTB has no Q3 installment. That September payment isn’t credited toward January’s bill — it just sits there as an overpayment. Meanwhile, owners who didn’t send enough in April and June still get hit with an underpayment penalty.

The two schedules side by side

The IRS spreads estimated payments evenly: 25% of your annual liability is due in April, June, September, and January. California takes a different approach.

California requires 30% in April and 40% in June — meaning 70% of your annual California liability is due by mid-June. The September payment is skipped entirely, and the remaining 30% is due January 15.

Due date	IRS (federal)	California FTB
April 15	25%	30%
June 15	25%	40%
September 15	25%	— (no payment)
January 15	25%	30%

Why the June payment is the one to prepare for

The June 15 payment is the largest single tax obligation most self-employed California owners face in a given year. It covers:

40% of your California estimated income tax liability
25% of your federal estimated income tax liability
The California PTET prepayment, if your S-corp or partnership elected it — this must also be paid by June 15 to get the deduction in the current year

Owners who aren’t tracking both schedules often look at June 15 only through the federal lens (25%) and underpay California. The FTB’s penalty isn’t catastrophic, but it’s avoidable.

New California businesses: an extra April complication

If you recently formed a California LLC, the $800 LLC annual fee (Form 3522) is also due April 15 — in addition to your Q1 estimated tax payment. New LLCs formed in the prior year owe the fee for that year. LLCs formed in the current year owe it within 3.5 months of formation.

That stacks April 15 with: personal return or extension, Q1 federal estimated payment, Q1 California estimated payment, and the $800 LLC fee. Planning cash flow around April 15 is worth doing explicitly.

How to calculate your California quarterly payments

The simplest approach is the safe harbor method: take last year’s total California tax liability from your 540, and distribute it 30/40/0/30 across the four due dates. You avoid underpayment penalties regardless of how this year turns out.

If income is meaningfully higher this year, the safe harbor can result in a large balance due at filing. In that case, recalculate based on projected current-year income instead.

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Frequently asked

Questions owners actually ask

Why does California have a different quarterly schedule than the IRS?: California set its own schedule independently of the federal government. The FTB requires a larger payment upfront (Q1 + Q2 combined = 70% of the year's liability) compared to the IRS's even 25% per quarter. The practical effect is that California owners need more cash available in April and June.
What happens if I pay California on the federal schedule (25% each quarter)?: If you pay 25% in April instead of 30%, you're underpaying Q1 by 5% of your annual estimate. The FTB will charge an underpayment penalty on that shortfall even if your total payments for the year are correct. The penalty rate is modest but avoidable.
Is there really no California payment due in September?: Correct. The federal Q3 payment is due September 15 — California has no Q3 payment. Your next California payment after June 15 is January 15 of the following year. Sending a California payment in September is voluntary prepayment, not a required installment.
What are the exact California estimated tax due dates?: Q1: April 15 (30% of annual estimate). Q2: June 15 (40% of annual estimate). Q3: No California payment due. Q4: January 15 of the following year (30% of annual estimate). These dates can shift if they fall on a weekend or holiday.
How does the California safe harbor work for estimated taxes?: If you pay 100% of your prior year California tax liability, distributed according to the CA schedule (30/40/0/30), you avoid underpayment penalties regardless of what you actually owe this year. This is useful when income is hard to predict.
Does the PTET payment change my quarterly estimated tax requirements?: Yes. When an S-corp or partnership makes a PTET prepayment by June 15, that can reduce or eliminate your personal California estimated tax obligation — because the entity is paying California income tax on your behalf at the entity level. The personal California credit from PTET means you may owe nothing personally on that income.

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Educational content only.This article is for informational purposes and does not constitute tax, legal, or investment advice. Every owner’s facts are different; consult a qualified CPA and advisor before acting. Tax and accounting services are provided through Matt Reese, CPA; investment advisory services are provided through Measured Risk Portfolios, a registered investment adviser. Matt Reese, CPA and Measured Risk Portfolios are separate entities; clients are not required to engage both.