3539: Payment for Automatic Extension for Corps and Exempt Orgs (2025)

Who files this form

Use Form FTB 3539 only if both apply:

• Your corporation or exempt organization cannot file its 2025 California tax return by the original due date.
• It owes tax for the 2025 taxable year.

Use the Tax Payment Worksheet to determine whether tax is due. Do not file Form FTB 3539 if no tax is due or if you pay electronically.

An LLC that elects to be taxed as a corporation for federal tax purposes is treated as a corporation under these instructions. Enter its FEIN and California Secretary of State file number, if applicable.

For a combined unitary group filing a single return, only the designated key corporation submits Form FTB 3539. If members file separate returns, each member submits its own form when its worksheet shows tax due, unless paying electronically.

When it's due

Calendar-year 2025 deadlines

| Return filed | Tax payment due | Extended return filing deadline |

| --- | --- | --- |

| Form 100 or 100W | April 15, 2026 | November 16, 2026 |

| Form 100S | March 16, 2026 | September 15, 2026 |

| Form 100 for a farmers’ cooperative | September 15, 2026 | April 15, 2027 |

| Form 109, generally | May 15, 2026 | November 16, 2026 |

| Form 109 for an employees’ trust under IRC 401(a) or an IRA | April 15, 2026 | October 15, 2026 |

Fiscal-year deadlines for the 2025 form

Each deadline below is the 15th day of the listed month following the close of the taxable year.

| Return filed | Tax payment due | Extended return filing deadline |

| --- | --- | --- |

| Form 100 or 100W | 4th month | 11th month |

| Form 100S | 3rd month | 9th month |

| Form 100 for a farmers’ cooperative | 9th month | 16th month |

| Form 109, generally | 5th month | 11th month |

| Form 109 for an employees’ trust under IRC 401(a) or an IRA | 4th month | 10th month |

An extension to file is not an extension to pay. Pay the tax by the original due date. When a due date falls on a weekend or holiday, the deadline to file and pay without penalty moves to the next business day.

What you'll need

Have these details ready to complete the form and worksheet:

• Corporation or exempt organization name, address, and telephone number.
• California corporation number, FEIN, and California Secretary of State file number, as applicable.
• Beginning and ending dates if filing for a fiscal year.
• The return the payment is for: Form 100, 100W, 100S, or 109.
• Total tentative tax, including alternative minimum tax if applicable.
• Estimated tax payments and any prior-year overpayment applied as a credit. S corporations may include QSub annual tax payments.

If paying by mail, include a check or money order with Form FTB 3539. Keep the completed Tax Payment Worksheet permanently with a copy of the California tax return.

How to file

Calculate the payment

1. Enter total tentative tax on worksheet line 1, including alternative minimum tax if applicable. Follow the worksheet rules for minimum franchise tax and QSub annual tax.
2. Enter estimated tax payments and prior-year overpayment credits on line 2.
3. If line 1 is greater than line 2, subtract line 2 from line 1. Enter the tax due on line 3 and on Form FTB 3539.

Pay electronically

The printed options are:

• EFT: Visit ftb.ca.gov and search for “eft.”
• Electronic Funds Withdrawal: Extension payments may be made through tax preparation software that supports this option.
• Web Pay for Businesses: Visit ftb.ca.gov/pay. Pay immediately or schedule a payment up to a year in advance.
• Credit card: Visit officialpayments.com. A convenience fee applies.

Do not mail Form FTB 3539 when paying electronically. Complete and keep the worksheet for your records.

Pay by mail

If tax is due and you are not paying electronically:

1. Complete Form FTB 3539.
2. Using black or blue ink, make your check or money order payable to “Franchise Tax Board.” It must be in U.S. dollars and drawn against a U.S. financial institution.
3. Write the California corporation number, FEIN, or California Secretary of State file number and “2025 FTB 3539” on the payment.
4. Enclose the payment with the form, but do not staple them together.
5. Mail by the original return due date to:

FRANCHISE TAX BOARD

PO BOX 942857

SACRAMENTO CA 94257-0531

Common mistakes

• Waiting until the extended filing deadline to pay. Tax is due by the original return due date. Late payment can result in penalties and interest.
• Mailing an unnecessary voucher. Do not mail Form FTB 3539 if no payment is due or if you pay electronically.
• Ignoring mandatory electronic payment rules. An estimated tax or extension payment over $20,000, or total tax liability over $80,000, triggers the electronic payment requirement. The first payment that triggers it does not have to be electronic, but all subsequent payments must be. A 10% non-compliance penalty applies for using another method when electronic payment is required.
• Assuming the extension always applies. You must file by the extended due date, and your powers, rights, and privileges must not be suspended or forfeited by the FTB or California Secretary of State as of the original due date.
• Stapling the payment to the form. Enclose it without staples.
• Entering minimum franchise tax where it does not apply. Political action committees and exempt homeowners’ associations filing Form 100 should not enter minimum franchise tax on worksheet line 1.

Questions people ask

Do I need to submit a written request for an automatic extension?

No. To qualify, file the California tax return by the extended due date and make sure the organization’s powers, rights, and privileges are not suspended or forfeited by the FTB or California Secretary of State as of the original due date.

What if my payments and credits exceed my tentative tax?

If worksheet line 2 exceeds line 1, no tax is due. Do not mail Form FTB 3539. You still must file the return by the extended due date and meet the good-standing requirements.

Does paying 90% of the tax eliminate interest?

No. The FTB may waive the late payment penalty for reasonable cause. Reasonable cause is presumed if you pay 90% of the tax shown on the return by the original due date, but not less than the minimum franchise tax if applicable. Interest is mandatory.

What if one member of a combined unitary group must pay electronically?

All members must pay electronically if any member meets the mandatory EFT requirements, regardless of whether they file a single return or separate returns.

Official sources

• https://www.ftb.ca.gov/forms/2025/2025-3539.pdf