MO-NAI: Nonapportionable Income Schedule (Revision 2025-12)

Who files this form

Complete Form MO-NAI only if your corporation:

• Apportions income to Missouri and other states using Method Two A or, if applicable, Method Seven; and
• Has classified income as nonapportionable income.

All income is presumed to be apportionable unless you can clearly show that it is nonapportionable.

What you'll need

Have the following information and documents ready:

• Corporation name, taxable-year beginning and ending dates, Missouri Tax I.D. Number, Federal Employer I.D. Number, and charter number.
• A detailed description of your regular business operations, including your products or services. Include your NAICS code if you reported one on your federal tax return for this tax period.
• Gross income and related expense amounts, both everywhere and for Missouri.
• A detailed explanation of why each item is nonapportionable, including what puts it outside the scope of your regular business operations.
• Additional schedules or statements if you need more space.

If you previously received a Letter Ruling, Final Decision, binding agreement, or other legal document classifying a listed income item as nonapportionable, attach a copy. This applies to documents from the Missouri Department of Revenue, Missouri Administrative Hearing Commission, or a Missouri court of competent jurisdiction.

How to file

1. Enter the corporation’s identifying information and taxable-year dates.
2. Describe your regular business operations and explain why the listed income is nonapportionable.
3. Enter gross income in Columns 1 and 2 and related expenses in Columns 3 and 4, then total each column.
4. Subtract Column 3 from Column 1 for nonapportionable income everywhere. Enter the result on Form MO-MS, Part 1, Line 7.
5. Subtract Column 4 from Column 2 for Missouri-allocated nonapportionable income. Enter the result on Form MO-MS, Part 1, Line 9.
6. Attach Form MO-NAI to Form MO-1120 and mail it to the Missouri Department of Revenue at the applicable address below.

Balance due:

Missouri Department of Revenue

P.O. Box 3365

Jefferson City, MO 65105-3365

Refund or no amount due:

Missouri Department of Revenue

P.O. Box 700

Jefferson City, MO 65105-0700

Common mistakes

• Leaving the schedule off your return. The form warns that your nonapportionable income will not be considered if this schedule is not attached to your Corporation Income Tax Return.
• Treating income as nonapportionable without clearly showing why. All income is presumed to be apportionable unless you clearly show otherwise.
• Leaving out information because you ran out of space. Attach additional schedules or statements when needed.
• Omitting a prior legal determination. If you previously received a qualifying legal document classifying a listed item as nonapportionable, attach a copy.

Questions people ask

What is nonapportionable income?

The form defines it as all income other than apportionable income. You must explain in detail why the income falls outside the scope of your regular business operations.

What does apportionable income include?

It includes income from transactions and activities in the regular course of the corporation’s business. It also includes income from tangible or intangible property when its acquisition, management, employment, development, or disposition is or was related to the business’s operation.

Can rental income from business equipment be apportionable?

Yes. The form gives an example of a heavy construction business making short-term leases of cranes and tractors when they are not needed for a project. That rental income is apportionable.

Do I need to include my NAICS code?

Yes, if you reported a NAICS code on your federal tax return for this tax period. Include it with your written business description.

What if I need more room for my explanation?

Attach additional schedules or statements if you run out of space on Page 1 of Form MO-NAI.

Official sources

• https://dor.mo.gov/forms/MO-NAI.pdf