California | Personal Tax Extension | Form FTB 3519 | Payment for Automatic Extension for Individuals

California Personal Tax Extension Guide for 2025

Introduction to California Tax Extensions:

California residents benefit from an automatic extension to file their state personal income tax return. Unlike many other states, California does not require taxpayers to submit a separate form to receive this extension. However, this automatic extension only applies to the filing of the return—not the payment. Any taxes owed must still be paid by the original due date to avoid penalties and interest.

Personal Tax Extension Requirements:

To qualify for California’s automatic personal tax extension, you must file your return by the extended due date of October 15, 2025. You do not need to submit a request or file Form FTB 3519 unless you are making a payment. If you owe taxes, you must pay by April 15, 2025, using Web Pay or by submitting Form FTB 3519 along with your payment.

Forms, Deadlines, and Payment Details for Personal Extensions:

The primary form associated with California’s tax extension process is Form FTB 3519. This form is used when making a payment toward any balance due by the original April 15 deadline. No form is required to get the extension itself; it is granted automatically. Payments can be made online through the Franchise Tax Board’s Web Pay system or via check using Form FTB 3519.

Mail all paper-based payments, along with Form FTB 3519, to the following address:

Franchise Tax Board
P.O. Box 942867
Sacramento, CA 94267-0008

Instructions for Filing Personal Tax Extensions:

1. Determine if you owe taxes for 2024. If yes, calculate the amount due.

2. Visit www.ftb.ca.gov/pay to make an electronic payment using Web Pay, or complete Form FTB 3519 if paying by check.

3. Submit payment by April 15, 2025.

4. File your completed California state tax return by October 15, 2025.

Common Mistakes to Avoid:

• Assuming the extension applies to payments—It does not. You must pay by April 15 to avoid penalties.

• Failing to check Web Pay confirmation—Always retain your confirmation number.

• Not estimating tax due—Use prior year tax data if necessary.

• Mailing Form FTB 3519 late—Ensure timely postmark if sending payment by check.

Penalties & Interest for Late Filing or Payment:

California assesses a late filing penalty of 5% of the unpaid tax per month, up to a maximum of 25%. Late payment penalties include a one-time 5% penalty and an additional 0.5% per month, up to 40 months or 25% total. Interest is also charged on any unpaid amounts. Filing by the extended deadline while paying by April 15 can help avoid these penalties.

Who Should Consider a California Tax Extension:

• Freelancers and gig workers who experience variable income.

• Taxpayers waiting for corrected forms or late investment statements.

• Individuals undergoing life events such as marriage, relocation, or natural disaster impacts.

• Anyone needing additional time to organize deductions or contributions.

Making an Estimated Payment with Your Extension:

To make a payment, you can:

• Visit https://www.ftb.ca.gov/pay and use Web Pay with your bank account.

• Use a credit card through an authorized provider listed on the FTB website (fees apply).

• Mail a check with Form FTB 3519 to the FTB mailing address.

Tip: Paying at least 90% of your total 2024 tax liability can help you avoid underpayment penalties.

Key Points & Dates:

• Tax return due date: April 15, 2025

• Extension deadline: October 15, 2025

• No form required for the extension itself

• Use Form FTB 3519 only if making a payment

• Pay by April 15 to avoid penalties and interest