40: Form 40 - Corporation Income Tax Return (2025)
North Dakota · ND Tax Commissioner · Used for tax years 2025
North Dakota Form 40 is the Corporation Income Tax Return for 2025. It reports income apportioned or allocated to North Dakota, adjustments, exemptions, credits, tax liability, payments, and any balance due or overpayment.
Who files this form
Form 40 is North Dakota’s corporation income tax return for tax year 2025. It includes filing methods for a single corporation, combined reports, water’s edge returns, and consolidated returns.
The form states that a corporation required to use the worldwide unitary combined report method must use that method unless it elects the water’s edge method. The supplied text does not give a general rule for which corporations must file.
What you'll need
Gather the information and attachments that apply to your return:
- Corporation details: Name, mailing address, federal employer identification number (FEIN), business code, incorporation date, and telephone number.
- Federal income figures: Schedule SA refers to deductions on Federal Form 1120. Schedules WW and WE start with taxable income from consolidated Federal Form 1120.
- Supporting worksheets: Attach worksheets where requested for adjustments, income exemptions, loss carryforwards, and credits. Attach a statement for interest on United States obligations.
- Withholding: Attach Form 1099-MISC if reporting North Dakota income tax withheld on oil and gas royalties.
- Estimated-tax interest: Attach Form 40-UT when reporting interest on underpayment of estimated tax.
- Credit documentation: Attach the worksheets, documentation, or schedules requested for each credit claimed, including property tax clearances when required.
- Consolidated returns: Complete and attach all three parts of Schedule CR.
- Entity information: Attach names and FEINs for included disregarded single-member LLCs with North Dakota business activity or apportionment factors, and for captive REITs, when applicable.
How to file
- Mark the calendar-year or fiscal-year box and enter the corporation’s identifying information.
- Mark one filing-method circle on page 1, line 1. Complete Schedule SA regardless of filing method and the other schedules that apply.
- Complete the tax, payment, and balance-due or overpayment lines. Answer the required questions on page 2.
- Complete the officer signature, title, and date fields, and the preparer fields if applicable. Attach required schedules and supporting documents.
- Mail the return to:
Office of State Tax Commissioner
600 E. Boulevard Ave., Dept. 127
Bismarck, ND 58505-0599
Make any total payment due payable to ND State Tax Commissioner. The supplied text does not provide e-filing directions.
Common mistakes
- Using Schedule FACT for a consolidated return. Corporations using filing method b1 or c1 must use Schedule CR, Part II, instead.
- Leaving required questions unanswered. Page 2 says its questions must be answered.
- Missing property tax clearances. For credits on lines 6–14, 16, 18, or 22, a clearance is required for each county where the corporation has a 50% or greater interest in North Dakota real property. The requirement also applies to officers responsible for state tax filing or payment obligations. Missing copies may cause a credit to be disallowed.
- Using the wrong rounding. Round dollar amounts to whole dollars. Apportionment calculations call for six decimal places.
- Treating each water’s edge selection as a new election. Marking the circle in years two through five does not start a new five-year election. The election must be made on the originally and timely filed return.
Questions people ask
Can an overpayment go toward next year’s estimated tax?
Yes. Line 25a lets you credit part of your 2025 overpayment toward 2026 estimated tax, with a minimum credit of $5.
Will a refund under $5 be issued?
No. Line 25b states that no refund under $5 will be issued.
Does the water’s edge method have an additional tax?
Yes. Line 17 applies a surtax of 3.5% of North Dakota taxable income on line 15 to water’s edge filers only.
Which corporations use Schedule SA?
All corporations use Schedule SA for statutory adjustments, regardless of filing method.
Can the tax office discuss the return with the preparer?
The form includes an authorization allowing the North Dakota Office of State Tax Commissioner to discuss the return with the preparer.