Maine corporate income tax return

File the Maine corporate income tax return with the Maine Revenue Services by the 15th day of the 4th month after the fiscal year ends (April 15 for a calendar year) and pay any tax due. Most states follow the federal extension if one is filed.

When: By the 15th day of the 4th month after the fiscal year ends (April 15 for a calendar year).
Agency: Maine Revenue Services
Applies to: C corporations registered in Maine.
Source: www.maine.gov, read October 22, 2026

Jay explains

Maine taxes corporate income, so a C corporation doing business there files a state return with the Maine Revenue Services by the 15th day of the 4th month after the fiscal year ends (April 15 for a calendar year), the same day as the federal Form 1120. The state usually honors a federal extension to file, but not to pay. The form name and any minimum tax are on the state's site.

Next dates

For a calendar year company. Shown as the agency states them; if a date falls on a weekend, file before it.

April 15, 2027
April 15, 2028

Also in Maine

Maine annual report Maine annual report Maine annual report Maine nonprofit annual report Maine charitable organization license renewal Maine corporate estimated tax payment Maine pass through entity return Maine personal income tax return with business income Maine unemployment insurance wage report Maine annual withholding reconciliation Maine Paid Family and Medical Leave contributions Maine harassment prevention training (15 or more employees)

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