20C: Alabama Corporation Income Tax Return (2025)
Alabama · Alabama DOR · Used for tax years 2025
Form 20C is Alabama's Corporation Income Tax Return for 2025. It reports federal taxable income, adjustments to Alabama income, deductions, credits and payments to calculate the amount due or refund.
Who files this form
Form 20C is Alabama’s Corporation Income Tax Return. The form lists filing statuses for:
- Corporations operating only in Alabama.
- Multistate corporations using apportionment, percentage of sales, or separate accounting.
- Corporations filing a proforma return as part of an Alabama affiliated group.
The supplied form does not state the full rules for determining whether a corporation must file. Separate accounting requires prior written approval, which must be attached.
What you'll need
- A copy of the federal return. The form warns that the Alabama return is incomplete without it.
- Company information: federal employer identification number, federal business code, address, accounting method, incorporation details, and information about Alabama operations.
- Income and payment records: federal taxable income, Alabama adjustments, estimated payments, extension payments, credits, and any prior-year payment carryover.
- Alabama net operating loss records, if applicable: loss year, original loss amount, amounts used in prior years and this year, and the remaining unused loss.
- Balance sheet information: beginning- and end-of-year assets, liabilities, and shareholders’ equity. Attach statements for the items marked “attach statement” in Schedule F.
- Applicable schedules: the form refers to Schedule AB for related-member expenses, Schedule BC for credits, and Schedule CP-B for composite payments and electing pass-through entity credits.
- Prior written approval if using separate accounting.
- Form BIT-V payment voucher when mailing a payment return.
How to file
The form provides these mailing addresses:
Returns without payment
Alabama Department of Revenue
Income Tax Administration Division
Corporate Tax Section
PO Box 327430
Montgomery, AL 36132-7430
Returns with payment
Mail with payment voucher Form BIT-V to:
Alabama Department of Revenue
Income Tax Administration Division
Corporate Tax Section
PO Box 327435
Montgomery, AL 36132-7435
Federal audit change returns
Alabama Department of Revenue
Income Tax Administration Division
Corporate Tax Section
PO Box 327451
Montgomery, AL 36132-7451
Sign and date the return, and include your title and daytime telephone number. Attach a copy of the federal return. Do not submit page 5 with Form 20C or BIT-V.
Common mistakes
- Leaving out the federal return. Form 20C is considered incomplete without a copy attached.
- Checking multiple federal-form boxes. The form says to check only one box identifying the form filed for federal purposes.
- Using Schedule D-2 when Alabama sales exceed $100,000. The form expressly prohibits this.
- Entering negative amounts on Schedule D-1. Amounts must be positive values.
- Using separate accounting without attaching prior written approval. Approval is required.
- Including page 5 with the filing. The form says not to submit that page with Form 20C or BIT-V.
Questions people ask
How is Alabama income tax calculated on the main form?
Line 15 calculates Alabama income tax as 6.5% of Alabama taxable income on line 14. Schedule D-2 separately directs percentage-of-sales filers to multiply Alabama gross receipts from sales by .0025 and carry that result to line 15.
Where do I report an Alabama net operating loss deduction?
Use Schedule B to calculate the Alabama net operating loss carryforward. Enter the deduction on page 1, line 13.
Can I apply an overpayment to next year’s estimated tax?
Yes. Line 21a provides a place to apply an overpayment to the subsequent year’s estimated tax.
Can the Department of Revenue discuss my return with my preparer?
The form has an authorization checkbox allowing a Department of Revenue representative to discuss your return and attachments with your preparer.