California collects state income tax from most workers, and the rate depends on how much you earn

California has a progressive income tax system, which means the tax rate increases as your income increases. Unlike a flat tax, where everyone pays the same percentage, California uses tax brackets — income ranges that each have their own rate. The lowest bracket starts at 1% for residents earning under a certain threshold, and the highest bracket reaches 13.3% for the highest earners in the state.

You pay California state income tax if you live in California and earn income from wages, self-employment, investments, or retirement accounts. The state also taxes non-residents on income they earned while working in California. The tax is withheld from paychecks automatically if you work for an employer, or you pay it yourself if you're self-employed or have investment income.

The amount you owe changes each year because California adjusts the tax brackets for inflation. This means the income ranges that fall into each bracket shift upward annually, so your tax rate may stay the same even if your income increases slightly.

Key Takeaways

  • California's income tax rates range from 1% to 13.3%, with higher rates applying to higher income levels.
  • Your employer withholds state income tax from your paycheck, or you pay it directly if you're self-employed.
  • Tax brackets adjust each year for inflation, so the income ranges that determine your rate change annually.
  • You file a California state tax return (Form 540) by April 15 if you earned income in the state during the previous year.
  • Certain types of income, like Social Security benefits and some retirement distributions, may be partially or fully exempt from California state tax.

The tax brackets and rates for 2024

California's tax brackets for 2024 apply to income earned during the 2023 tax year (filed in 2024). The brackets are different for single filers, married couples filing jointly, and heads of household. A single filer with taxable income under $10,099 pays 1%; income from $10,099 to $23,942 is taxed at 2%; and the rates continue to climb through higher brackets.

The highest bracket — 13.3% — applies to single filers with taxable income over $680,063. For married couples filing jointly, that same 13.3% rate applies to income over $1,360,126. These thresholds change annually. The state also imposes a 1% Mental Health Tax on income over $1 million for all filers, which is separate from the regular income tax brackets.

Because brackets shift each year, you should check the current year's rates on the California Franchise Tax Board website before calculating what you owe. The FTB publishes updated brackets by January of each year.

How withholding works and what affects your paycheck

If you work for an employer in California, your company withholds state income tax from your paycheck based on the W-4 form you complete when you're hired. The W-4 tells your employer how much to withhold by asking about your filing status, number of dependents, and other income. The more dependents or adjustments you claim, the less your employer withholds.

Withholding is an estimate. If your employer withholds too much, you'll receive a refund when you file your tax return. If too little is withheld, you'll owe money. You can adjust your withholding at any time by submitting a new W-4 to your employer — for example, if you get married, have a child, or take a second job.

Self-employed people and those with investment income don't have an employer to withhold taxes, so they typically make estimated tax payments four times a year (quarterly) to the California Franchise Tax Board. These payments are due in April, June, September, and January.

Filing your California state tax return

Most California residents file their state tax return using Form 540 (or Form 540-2EZ for simpler situations). The return is due by April 15 of the year following the tax year — so income earned in 2023 is reported on a return filed by April 15, 2024. If you file a federal return, you almost always need to file a California return as well.

You can file by mail, electronically through the FTB website, or through tax software that supports California returns. Electronic filing is faster and reduces errors. If you can't file by April 15, you can request an extension, though this extends only the filing deadline — taxes still owe by April 15.

When you file, you report all income sources: wages from your W-2, self-employment income, interest, dividends, and retirement distributions. You also claim any deductions or credits you're may have access to to, such as the standard deduction or dependent exemptions. The FTB uses your return to calculate whether you overpaid or underpaid during the year.

Income that is taxed differently or not at all

Not all income is taxed at the same rate, and some income is exempt from California state tax entirely. Social Security benefits are generally not taxed by California, even though they may be taxed federally. Certain retirement distributions, including some from IRAs and 401(k)s, may also be partially exempt depending on your age and income level.

Long-term capital gains (profits from selling investments held over one year) are taxed as ordinary income in California, unlike the federal system where they receive preferential rates. Interest from municipal bonds issued by California is exempt from state tax. Disability insurance benefits and workers' compensation are also exempt.

If you're unsure whether a specific type of income is taxable in California, the FTB website lists exemptions and special rules. Your tax software or a tax preparer can also clarify your situation.

Credits and deductions that lower your tax bill

California offers a standard deduction that reduces your taxable income before tax is calculated. For 2024 (tax year 2023), the standard deduction is $4,803 for single filers and $9,606 for married couples filing jointly. If you have significant deductible expenses — such as mortgage interest, property taxes, or charitable donations — you may benefit from itemizing deductions instead of taking the standard deduction.

The state also offers tax credits, which directly reduce the tax you owe rather than reducing your income. The Earned Income Tax Credit (EITC) is available to lower-income workers and families. The Child and Dependent Care Credit helps offset childcare costs. Other credits exist for education expenses, renewable energy installations, and other specific situations.

To claim credits and deductions, you list them on your tax return. Tax software typically walks you through questions to determine which ones apply to you. If you're not sure whether you may have access to for a specific credit, the FTB website has detailed descriptions, or you can contact a tax preparer.

What happens if you don't pay or file

If you owe California state income tax and don't pay by April 15, the state charges a failure-to-pay penalty of 0.5% of the unpaid tax per month, up to 25%. Interest also accrues on the unpaid balance at a rate set quarterly by the FTB. If you file late without a valid extension, you face an additional failure-to-file penalty.

If you don't file a return when you're required to, the FTB may file a return on your behalf based on information they have (such as W-2s from employers). This return often results in a higher tax bill than you would have calculated yourself because it doesn't include deductions or credits you might claim.

If you can't pay the full amount by April 15, you can request a payment plan with the FTB. The state offers installment agreements that allow you to pay over time, though interest and penalties continue to accrue. Contacting the FTB before the deadline is better than ignoring the debt, as it can reduce penalties and show good faith.

Frequently Asked Questions

Do I have to file a California state tax return if I only lived there part of the year?

Yes, if you earned income while living in California, you must file a California return for that year. You report only the income you earned during the months you were a resident. If you moved to another state mid-year, you may also owe taxes to that state on income earned there. Some states have reciprocal agreements that prevent double taxation.

What's the difference between California state tax and federal income tax?

Federal income tax goes to the U.S. government and funds national programs. California state tax goes to the state and funds California-specific programs like education, infrastructure, and social services. Both are withheld from your paycheck, and you file separate returns for each. The tax rates, brackets, deductions, and credits are different for each.

Can I claim dependents on my California return?

California allows a dependent exemption of $499 per dependent for the 2024 tax year (income earned in 2023). This reduces your taxable income. You must claim the same dependents on your California return as you do on your federal return. The dependent must have a valid Social Security number and meet relationship and residency requirements.

What if I'm retired and living on a fixed income?

Retirees may owe California state tax depending on the source of their income. Social Security is generally not taxed. Distributions from traditional IRAs and 401(k)s are taxable as ordinary income. Pensions may be partially exempt if you're over 55 and meet other conditions. You still file a return if your income exceeds the filing threshold for your age and filing status.

How do I know if the California Franchise Tax Board is contacting me legitimately?

The FTB contacts taxpayers by mail, not by phone or email, for most matters. Scammers often impersonate the FTB to steal personal information. If you receive a call or email claiming to be from the FTB, do not provide information. Instead, contact the FTB directly using the phone number on their official website or on a tax notice you received in the mail.