2027 Alabama Tax Deadlines

Last updated: July 29, 2026

Key Alabama tax dates at a glance

This block is the single date reference for 2027 Alabama filing, payment, and extension planning.

• April 15, 2027: First estimated payment (calendar-year filers).
• June 15, 2027: Second estimated payment.
• September 15, 2027: Third estimated payment.
• January 18, 2028: Fourth estimated payment; also the qualifying-farmer payment date.
• March 15, 2028: S Corporation (Form 20S), Partnership (Form 65), and calendar-year Form PPT: file and pay.
• April 18, 2028: Individual return and payment; also the federal C Corporation date that sets Alabama's one-month-later corporate deadline.
• May 18, 2028: C Corporation (Form 20C): file and pay.
• September 15, 2028: Extended S Corporation and Partnership returns (file only).
• October 16, 2028: Extended Individual return (file only).
• November 16, 2028: Extended C Corporation return (file only).

When are Alabama taxes due in 2027?

Alabama due dates depend on taxpayer type: pass-through entities, Individuals, C Corporations, and estimated-payment taxpayers each follow a different pattern, all listed once in the key dates block above. Alabama separates the deadline to file from the deadline to pay: an extension buys more time to file, never more time to pay.

Instead AI helps tax teams turn Alabama filing, payment, and extension rules into an execution calendar while keeping entity-specific deadlines connected to advisor review instead of a generic state compliance checklist.

When is the Alabama C Corporation return due?

Alabama C Corporations file and pay corporate income tax by May 18, 2028, one month after the federal due date.

• Complete Form 20C (Alabama Corporation Income Tax Return).
• File online through My Alabama Taxes or approved software.
• Pay by the original Alabama due date.
• Postmark any mailed return by the due date.

What are Alabama C Corporation extension rules?

Alabama recognizes an accepted federal extension when the federal requirements are met, without a separate Alabama form. The extension is to file only; payment stays due on May 18, 2028.

When are Alabama S Corporation and Partnership returns due?

Alabama S Corporations and Partnerships file their Alabama income returns by March 15, 2028, using Form 20S and Form 65.

Which pass-through forms are required?

• Form 20S: S Corporation Return.
• Form 65: Partnership/LLC Return.
• Form PPT: Business Privilege Tax Return and Annual Report (calendar-year pass-through entities).

What are the pass-through extension rules?

A federal extension carries the Alabama return to September 15, 2028. The extension is for filing only; payment stays due on March 15, 2028.

When is the Alabama Individual income tax return due?

The Alabama Individual income tax return is due April 18, 2028. Alabama automatically grants a six-month filing extension with no separate form, but payment stays due April 18, 2028. Filing requirements depend on filing status and gross income.

Available returns:

• Form 40: Residents and part-year residents.
• Form 40A: Full-year residents.
• Form 40NR: Nonresidents.

What Alabama tax rates apply for 2027?

Alabama uses a graduated structure from 2% to 5%:

• 2% on the first $500 for single filers ($1,000 for married filing jointly).
• 4% on taxable income from $501-$3,000 for single filers ($1,001-$6,000 MFJ).
• 5% on taxable income above $3,000 for single filers ($6,000 MFJ).

When are Alabama estimated (quarterly) payments due?

Calendar-year taxpayers generally pay Alabama estimated tax on these dates:

• April 15, 2027: First estimated payment (calendar-year filers).
• June 15, 2027: Second estimated payment.
• September 15, 2027: Third estimated payment.
• January 18, 2028: Fourth estimated payment; also the qualifying-farmer payment date.

Who must make Alabama estimated payments?

You generally must pay Alabama estimated tax during 2027 if you expect to owe $500 or more after withholding and credits. Farmers may pay the full estimate by January 18, 2028, when at least two-thirds of gross income comes from farming. Alabama requires electronic payment for amounts of $750 or more.

What are the Alabama extension deadlines?

Alabama extension deadlines are September 15, 2028 for S Corporations and Partnerships, October 16, 2028 for Individual returns, and November 16, 2028 for C Corporations. The rule is the same across all three: an Alabama extension gives more time to file, not to pay. Tax due should be paid by March 15, 2028, April 18, 2028, or May 18, 2028, depending on return type.

What Alabama-specific rules should advisors watch for 2027?

Deadlines are only part of Alabama compliance. Review these against current Alabama Department of Revenue guidance:

• Mandatory e-filing for C Corporations and pass-through entities (tax year 2026 and later); preparers must use approved software.
• R&D expenses fully deductible in the year incurred for qualifying businesses.
• A 30-day safe harbor for nonresidents working temporarily in Alabama.
• For tax years beginning on or after January 1, 2024, businesses whose calculated Business Privilege Tax is $100 or less owe $0 and are not required to file the Business Privilege Tax return.
• Favorable treatment of Social Security, military retired pay, and many state and local government pensions.
• An annual pass-through entity tax election for eligible S Corporations and certain Partnerships, subject to credit limits.

For a complex position, use a qualified advisor or the accounting firm directory to find professional support.

Sources

• Alabama Department of Revenue: Due Dates
• Alabama Corporate Income Due Date Extensions
• Alabama Revenue Online Services
• Alabama Individual Income Tax

Alabama tax deadlines for entities and estimates

Alabama teams juggle corporate income-tax dates, pass-through owner work, local business obligations, and estimate cycles. Instead's AI-driven tax platform keeps each due date connected to the filing work, planning decisions, and fixed-asset records that support it.

Use filing to move returns through review and submission, then keep estimates and client follow-up organized before the next Alabama deadline. Built for tax professionals who want a better tax operation system to manage compliance and advisory work for clients.