Quarterly estimated taxes in California: a 2026 guide
When you’re self-employed, no one withholds tax from your income, so you pay it during the year in installments. California and the IRS both expect payments, but on different schedules.
By: Computatio · Last reviewed 2026-10-23
Do you need to pay estimated tax?
Federal: you generally must pay estimated tax if you expect to owe at least $1,000 for the year after withholding and refundable credits.
California: the threshold is lower. You generally must pay if you expect to owe at least $500 ($250 if married or in a registered domestic partnership filing separately).
Your federal amount covers both income tax and self-employment tax. Self-employment tax is 15.3% (12.4% Social Security and 2.9% Medicare) on 92.35% of your net earnings. The Social Security part applies only up to the 2026 wage base of $184,500.
2026 due dates
| Payment | IRS | California (FTB) |
|---|---|---|
| 1 | April 15, 2026: 25% | April 15, 2026: 30% |
| 2 | June 15, 2026: 25% | June 15, 2026: 40% |
| 3 | September 15, 2026: 25% | September 15, 2026: 0% |
| 4 | January 15, 2027: 25% | January 15, 2027: 30% |
California front-loads its payments: 70% of the year’s estimate is due by June 15, and nothing is due in September.
One federal exception: you can skip the January 15, 2027 IRS payment if you file your 2026 return by February 1, 2027 and pay the full balance with it.
How much to pay: the safe harbor rules
You avoid an underpayment penalty if your payments (plus any withholding) cover the smaller of:
- 90% of this year’s tax, or
- 100% of last year’s tax, or 110% if last year’s adjusted gross income was over $150,000 ($75,000 if married filing separately).
California uses the same 90% / 100% / 110% tests, with one addition: if your California adjusted gross income this year is $1,000,000 or more ($500,000 if married or RDP filing separately), you must base payments on 90% of this year’s tax.
Using last year’s tax is the simplest method for most people. It works even if your income grows, as long as you pay on time.
Worked example (hypothetical)
Ana is a freelance designer in San Diego. Her 2025 adjusted gross income was under $150,000. Her 2025 returns showed $12,000 total federal tax and $3,000 California tax.
- Federal: 100% of $12,000, split into four payments of $3,000.
- California: 100% of $3,000 on the 30/40/0/30 schedule: $900 on April 15, $1,200 on June 15, nothing on September 15, $900 on January 15, 2027.
If Ana’s 2026 income is much higher, she’ll still owe the difference when she files, but she won’t owe an underpayment penalty.
How to pay
- IRS: IRS Direct Pay from your bank account at no cost, or the Electronic Federal Tax Payment System (EFTPS). Choose “estimated tax” and the 2026 tax year.
- California: FTB Web Pay from your bank account. You can schedule a payment up to a year ahead. Paper payments use Form 540-ES vouchers.
Keep the confirmation numbers. You’ll enter the payments on your 2026 returns.
Set the money aside as you earn it
The due dates are easy. Having the cash ready is the hard part. A simple routine:
- Open a separate savings account just for taxes.
- Each time a client pays you, move a fixed share of the payment into it. Pick the share from last year’s total tax divided by last year’s income.
- Once a month, update and reconcile your books so your profit figure is current.
- A week before each due date, compare the savings balance with the payment you plan to make. Adjust your share if your income has changed.
If you use AI to project the year, check its math line by line. Our guide on using AI to estimate quarterly taxes shows how.
If you missed a payment
Pay as soon as you can. The federal underpayment penalty is figured separately for each due date, based on how much was short and how many days it stayed unpaid. So a late payment usually costs less than no payment. A later payment is applied first to the earliest unpaid installment.
If your income came in unevenly, for example most of it late in the year, the annualized income method on Form 2210 may lower or remove the federal penalty.
When estimated payments get large
If your profit keeps growing, look at how your business is set up. Some owners compare an S corporation with staying a sole proprietor. See S-corp vs. sole proprietor, and browse our other estimated tax guides.
Sources
- IRS: 2026 Form 1040-ES, Estimated Tax for Individuals
- FTB: 2026 Instructions for Form 540-ES
- IRS: Self-employment tax (Social Security and Medicare taxes)
- SSA: Contribution and benefit base
- IRS: Instructions for Form 2210
This guide is general information, not tax advice for your situation.