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California Business State Tax Extension I LLCs / Partnerships Filing Guide

FTB 3537 | Payment for Automatic Extension for LLCs  ·  LLCs / Partnerships  ·  Business Filing Guide

Overview

California LLCs and partnerships are subject to state tax filing requirements, administered by the California Franchise Tax Board. California automatically grants an extension to file with no application or form submission required.

Original Filing Deadline

The original due date for the California LLCs / Partnerships return is March 16, 2026. File or remit full payment by this date to remain in good standing.

Extension Granted Automatically

California automatically grants a filing extension for LLCs / Partnerships. The extended filing deadline is September 15, 2026. No application or form submission is required to receive this extension.

Payment Is Still Due by Original Deadline

The extension applies to filing only—it is not an extension to pay taxes owed. Any outstanding tax liability must be paid by the original due date of March 16, 2026 to avoid penalties and interest. Use the California | Online Tax Extension Payment to pay electronically. For mail-in payments, use FTB 3537 | Payment for Automatic Extension for LLCs and send to: Franchise Tax Board P.O. Box 942857 Sacramento, CA 94257-0531

Late Filing and Payment Penalties

• Failure to File: 5% of unpaid tax per month up to 25%.
• Failure to Pay: 5% of unpaid amount plus 0.5% per month up to a maximum of 25%.

Best Practices

• Estimate and pay your California business tax by March 16, 2026 to avoid interest and penalties.
• No extension form is required—California grants the extension automatically.
• Use the state online payment portal for fast, convenient electronic payment.
• Set a reminder to file your completed California LLCs / Partnerships return by September 15, 2026.

Final Thoughts

• California’s automatic extension simplifies the process—no paperwork required. Pay any balance due by March 16, 2026 and file your return by September 15, 2026.
• Quick Reference Table
• State Abbreviation
• CA
• State Name
• California
• Business Entity Type
• LLCs / Partnerships
• Extension Status
• Approved Automatically
• Return Due Date
• March 16, 2026
• Extended Due Date
• September 15, 2026
• Other Information
• California grants you an automatic 6-month extension to file your business tax return. The extension is NOT an extension to pay any taxes you may have due. Tax payments are due by the original return due date.
• Online Payment
• California | Online Tax Extension Payment
• Payment Voucher Form
• FTB 3537 | Payment for Automatic Extension for LLCs
• State Payment Agency
• California Franchise Tax Board
• Mailing Address with Payment
• Franchise Tax Board P.O. Box 942857 Sacramento, CA 94257-0531
• Failure to File Penalties
• 5% of unpaid tax per month up to 25%.
• Failure to Pay Penalties
• 5% of unpaid amount plus 0.5% per month up to 25%.

Working with a Tax Professional

Business tax returns are complex—a licensed CPA or Enrolled Agent can maximize deductions, ensure accurate calculations, and handle filing on your behalf. Here's how working with a TaxPro typically goes:

1. 1Get matched with a verified U.S.-based CPA or Enrolled Agent
2. 2Upload your business documents via secure drag-and-drop
3. 3Review and approve your return with upfront, transparent fees
4. 4Your TaxPro files your California return by September 15, 2026

Quick Reference Table

State Abbreviation	CA
State Name	California
Business Entity Type	LLCs / Partnerships
Extension Status	Approved Automatically
Return Due Date	March 16, 2026
Extended Due Date	September 15, 2026
Other Information	California grants you an automatic 6-month extension to file your business tax return. The extension is NOT an extension to pay any taxes you may have due. Tax payments are due by the original return due date.
Online Payment	California | Online Tax Extension Payment
Payment Voucher Form	FTB 3537 | Payment for Automatic Extension for LLCs
State Payment Agency	California Franchise Tax Board
Mailing Address with Payment	Franchise Tax Board P.O. Box 942857 Sacramento, CA 94257-0531
Failure to File Penalties	5% of unpaid tax per month up to 25%.
Failure to Pay Penalties	5% of unpaid amount plus 0.5% per month up to 25%.