California State Tax Guide for International Students

California is home to more international students than any other state - over 200,000 at last count. If you're one of them, and you earned income in California during the tax year, you need to file a California state tax return.

This guide covers everything F1 students need to know about California state taxes.

Do I Need to File California State Taxes?

You need to file a California state tax return if:

You earned income from California sources AND:

Your gross income exceeded $20,913 (single) in 2025

You have California source income and are required to file a federal return

You want a refund of California taxes withheld

California source income includes:

Wages from a California employer

Income from California-based freelance work

Rental income from California property

Certain scholarship/fellowship income paid by California institutions

You likely DON'T need to file if:

You only worked in a different state

You had no income at all

Your only income was from sources outside California (and outside the U.S.)

Which California Tax Form Do F1 Students Use?

As a nonresident for federal tax purposes, you're also typically a nonresident for California tax purposes. You'll file:

Form 540NR - California Nonresident or Part-Year Resident Income Tax Return

This is different from the regular Form 540 that California residents use.

California Tax Rates for 2025

California has a progressive income tax with rates ranging from 1% to 12.3%:

As a nonresident, you're only taxed on your California-source income, not your total income.

What You'll Need to File

Documents:

W-2 from your California employer (Box 16 shows California wages, Box 17 shows California tax withheld)

Your completed federal tax return (you must complete federal first)

1099 forms for any California-source income

Information:

Your California address during the tax year

Dates you were present in California

Details about income earned in other states (if any)

Step-by-Step: Filing California State Taxes

Step 1: Complete your federal return first

California requires information from your federal return (Form 1040-NR), so always finish federal taxes before starting state.

Step 2: Determine your California residency status

Most F1 students are California "nonresidents" - meaning California is not your permanent home. You're just here temporarily for education or OPT.

Step 3: Calculate California source income

Add up all income you earned from California sources. This is typically your W-2 Box 16 amount.

Step 4: Complete Form 540NR

Enter your California income, calculate tax using the California tax tables, and subtract any California tax already withheld (from W-2 Box 17).

Step 5: Determine if you owe or get a refund

If your employer withheld more California tax than you owe → refund

If your employer withheld less than you owe → payment due

California Tax Deadline

The California state tax deadline is April 15, 2026 for tax year 2025 - the same as the federal deadline.

If you can't file by April 15, California offers an automatic 6-month extension to file (but not to pay). You'd need to file by October 15, 2026.

Do I Need to Pay California Taxes If I Moved Mid-Year?

This is common for OPT students who start jobs in different states. Here's how it works:

If you worked in California for part of the year:

File as a "part-year resident" or "nonresident"

Only pay California tax on income earned while working in California

File Form 540NR

If you moved FROM California TO another state:

File California 540NR for income earned while in California

File that state's tax return for income earned there

If you worked remotely for a California company from another state:

Generally, you're taxed based on where you physically worked

If you worked from Texas (no state tax), you may not owe California tax even if your employer is in California

However, rules vary - consult the specific circumstances

Common Mistakes F1 Students Make on California Taxes

Mistake 1: Using the wrong form

Filing Form 540 (resident) instead of Form 540NR (nonresident) is a common error. Make sure you're using the nonresident form.

Mistake 2: Forgetting to file California taxes entirely

Some students file federal returns but forget about state. If California tax was withheld from your paycheck, you need to file to get your refund.

Mistake 3: Not reporting all California income

If you had multiple California employers or income sources, include all of them.

Mistake 4: Filing before completing federal

California calculations depend on your federal return. Always do federal first.

California Tax for Students with No Income

If you had no California income, you generally don't need to file a California state return. Form 8843 is a federal form only - there's no state equivalent.

However, if California taxes were withheld from a scholarship or fellowship payment, you may want to file to claim a refund.

The Easy Way: F1TaxReturn Handles California

Figuring out Form 540NR on your own is tedious. F1TaxReturn does it automatically:

We pull in your federal return data

Calculate your California tax liability

Apply any credits or deductions you qualify for

Generate a ready-to-file California return

All for just $30 - compared to $50+ elsewhere.