Quarterly estimated taxes in California: who has to pay them, and how they work

Who this applies to

Estimated taxes exist because the United States collects income tax as income is earned, not in one payment at the end. An employee satisfies this through payroll withholding. Everyone else pays it directly.

That includes sole proprietors and single-member LLCs filing Schedule C, independent contractors, partners drawing distributions, people with meaningful investment or rental income, and retirees who have not set up withholding on distributions. It also includes employees whose withholding no longer matches reality, which happens after a raise, a bonus, equity vesting, or a spouse starting work.

The federal rules

You generally must make federal estimated payments if both of the following are true: you expect to owe at least $1,000 in tax after subtracting withholding and refundable credits, and your withholding and credits are expected to be less than the smaller of two safe harbors.

The safe harbors are the useful part. Meet either one and you avoid the underpayment penalty regardless of how much you ultimately owe.

• 90 percent of the current year’s tax. Useful when income is falling or predictable.
• 100 percent of the prior year’s tax, taken from the return you already filed. This rises to 110 percent if your adjusted gross income on that prior return was more than $150,000, or more than $75,000 if married filing separately.

The prior-year safe harbor is the one most growing businesses should use. It is a known number. You are not forecasting anything. If you have a very good year, you will owe more in April, but you will not owe a penalty on top of it.

Federal due dates

The quarters are not equal in length. The second covers two months and the third covers three. This is deliberate and it is not a typo on the form.

Where California is different

Three differences matter, and each one catches people.

A lower trigger

California generally requires estimated payments if you expect to owe at least $500 after withholding and credits, or $250 if married or in a registered domestic partnership filing separately. Someone with a modest side business can clear California’s threshold while sitting comfortably under the federal one, and that person owes state estimates but not federal ones.

A front-loaded schedule

California does not ask for four equal payments. The required annual amount is due in this pattern:

Seventy percent of the year is due by June 15. A business owner who sets aside one quarter of the annual estimate each quarter is underpaid on both of the first two California installments, and the penalty runs from those dates even if the total is right by January.

The third installment is genuinely zero. Nothing is due in September for California. People who have internalized the federal rhythm often send a payment anyway, which is harmless, and people who have internalized the California rhythm sometimes skip September federally, which is not.

A different safe harbor at the top

California follows the same general 90 percent and 100 percent, or 110 percent above $150,000, structure as the federal rules. But taxpayers with California adjusted gross income of $1,000,000 or more — $500,000 or more if married or an RDP filing separately — must base estimates on 90 percent of the current year’s tax. The prior-year safe harbor is not available to them.

Mandatory electronic payment

California requires certain individuals to pay electronically from that point forward. The requirement is triggered when you make an estimated tax or extension payment exceeding $20,000, or when you file an original return with a total tax liability over $80,000. Once triggered, all subsequent payments must be made electronically, and paying by check afterward carries a penalty. The obligation continues until the Franchise Tax Board grants a waiver.

How to size the payment

For a first year in business, with no prior-year figure to lean on, a workable starting point is to set aside roughly 25 to 35 percent of net profit, adjusted for your other income and filing status. That range is a planning heuristic, not a rule, and it is deliberately wide because self-employment tax, marginal bracket, and California’s rates all move it.

After the first year, switch to the prior-year safe harbor. Take the total tax from last year’s return, apply 100 or 110 percent depending on your AGI, divide it across the federal quarters and across California’s 30/40/0/30 pattern, and pay that. It removes the forecasting problem entirely.

If your income arrives unevenly — a consultant with two large invoices, a seller with a fourth-quarter season — the annualized income installment method lets you match payments to when the income actually arrived. It is computed on Form 2210 federally and Form 5805 for California. It is more work, and for genuinely lumpy income it is often worth it.

Paying

Federal payments go through IRS Direct Pay, the Electronic Federal Tax Payment System, or your online account, using Form 1040-ES vouchers if paying by mail. California payments go through Web Pay on the Franchise Tax Board site, using Form 540-ES if paying by mail.

Two habits prevent most problems. Pay from a separate account that only holds tax money, so the balance is never spent by accident. And record every payment with its date and confirmation number as you make it, because reconciling four federal and three California payments in April from bank memory is where errors get introduced.

Common questions

How much do I have to expect to owe before estimated payments are required?

Federally, generally $1,000 or more after withholding and refundable credits. For California, generally $500 or more, or $250 if married or in a registered domestic partnership filing separately.

What is the safe harbor for estimated taxes?

Paying at least 90 percent of the current year's tax, or 100 percent of the prior year's tax, avoids the underpayment penalty. The prior-year figure rises to 110 percent if prior-year adjusted gross income exceeded $150,000, or $75,000 if married filing separately.

Why is nothing due to California in September?

California uses a front-loaded installment schedule of 30 percent in April, 40 percent in June, zero in September, and 30 percent in January. Seventy percent of the annual amount is due by June 15.

Does California have a different safe harbor for high incomes?

Yes. Taxpayers with California adjusted gross income of $1,000,000 or more, or $500,000 or more if married or an RDP filing separately, must base estimated payments on 90 percent of the current year's tax and cannot use the prior-year safe harbor.

When does California require me to pay electronically?

The mandatory e-pay requirement is triggered by making an estimated tax or extension payment over $20,000, or filing an original return showing a total tax liability over $80,000. All later payments must then be made electronically until the Franchise Tax Board grants a waiver.