Check Alabama tax deadlines for individuals and C Corporations. Confirm due dates, extension rules, and exemptions for S Corps and Partnerships.
This guide covers all Alabama state tax deadlines for Tax Year 2025, filed in 2026, including individuals, calendar-year and fiscal-year businesses, and special entity types.
Alabama Tax Deadlines at a Glance (2026)
Entity Type | Return Due | Extension |
|---|---|---|
Individuals | April 15, 2026 | October 15, 2026 |
C Corporations | April 15, 2026 | October 15, 2026 |
S Corporations | March 16, 2026 | September 15, 2026 |
Partnerships | March 16, 2026 | September 15, 2026 |
Trusts & Estates | April 15, 2026 | October 15, 2026 |
Business Privilege Tax | April 15, 2026 | No |
Individuals
Applies to residents, part-year residents, and non-residents with Alabama-source income. Extensions apply to filing only.
Businesses
C Corps: Taxed at entity level
S Corps & Partnerships: Informational return + withholding where applicable
LLCs: Follow tax classification; still subject to Business Privilege Tax
Fiscal-Year Entities
Returns are due the 15th day of the 4th month after year-end (C corps) or 3rd month (pass-throughs).
Special Entities
Nonprofits filing Alabama income tax returns
Financial institutions
Insurance companies
Disregarded entities with Alabama activity
Estimated Taxes (Individuals & Corporations)
Quarter | Due Date |
|---|---|
Q1 | April 15, 2026 |
Q2 | June 15, 2026 |
Q3 | September 15, 2026 |
Q4 | January 15, 2027 |
Common CPA Pitfalls
Missing Business Privilege Tax on inactive entities
Assuming federal extensions cover Alabama
Underpaying composite withholding