Montana taxes

Montana taxes personal income at 4.7% and 5.9%, with lower rates on long-term capital gains. A sole proprietor owes no separate business tax. LLCs, partnerships and corporations file a $20 annual report. Partnerships and S corporations file Form PTE and must withhold for, or otherwise cover, owners who live elsewhere. C corporations pay 6.75% corporate income tax, never less than $50.

Personal income tax

Montana residents file Form 2, due April 15, 2026. You automatically get six more months, to October 15, 2026, to file, but the tax is still due April 15, 2026.

Ordinary income is taxed at 4.7%, and at 5.9% above $21,100 of taxable income for single filers, $31,700 for head of household and $42,200 for married couples filing jointly. Long-term capital gains are taxed at 3% or 4.1%, depending on how much of that first bracket your other income has already used.

Montana starts from your federal taxable income, so it uses your federal standard or itemized deduction instead of one of its own. It does not allow the federal qualified business income deduction, which matters to business owners. Everyone 65 or older subtracts $5,660, at any income.

Return

Form 2

Due date

April 15, 2026, with an automatic extension to October 15, 2026

Rates

4.7% and 5.9%

5.9% starts above

$21,100 single or married filing separately, $31,700 head of household, $42,200 married filing jointly

Long-term capital gains

3% and 4.1%

Deduction

Your federal deduction, already taken out of federal taxable income

Qualified business income deduction

Not allowed

Age 65 and over

$5,660 subtracted for each person

Earned income credit

10% of the federal credit, refundable

Sole proprietor

A sole proprietor with no LLC files nothing with Montana for the business. The annual report is only for registered entities, and Montana has no sales tax.

Your business profit is taxed on your own Form 2, at the personal rates above.

Single-member LLC

Every Montana LLC files an annual report with the Secretary of State to confirm it is still active. The fee is $20 by April 15 and $35 after, whatever the business earned. Montana has waived the on-time fee in recent seasons, but it announces that each year, so check before you pay.

The LLC's profit is taxed on your own Form 2.

Partnership

A Montana partnership files Form PTE, due March 16, two months before the corporate return. The profit passes through to the partners, who report it on their own returns.

If a partner lives outside Montana, the partnership must withhold Montana tax on that partner's share, unless the partner signs Form PT-AGR and files their own Montana return, or the partnership chooses to pay composite tax for them on Form PTE, or chooses the pass-through entity tax. Those choices must be made by the extended due date.

A registered partnership, such as an LLC, also files the $20 annual report by April 15.

S corporation

A Montana S corporation files Form PTE, due March 16. The profit passes through to the shareholders, who report it on their own returns. The $50 minimum corporate tax does not apply.

For a shareholder who lives outside Montana, the corporation withholds Montana tax on their share, unless they sign Form PT-AGR and file their own Montana return, or the corporation chooses composite tax or the pass-through entity tax by the extended due date. It also files the $20 annual report by April 15.

C corporation

A C corporation files Form CIT, due May 15 for a calendar year, and pays 6.75% of the income apportioned to Montana. The tax is never less than $50, even in a loss year, and on a combined return each corporation owes its own minimum. A corporation that elects water's-edge filing pays 7% instead.

A corporation selling into other states counts only its Montana share, measured by Montana sales over total sales from 2025. It also files the $20 annual report by April 15.

Return

Form CIT, due May 15 for a calendar year

Corporate income tax

6.75% of Montana income, 7% for water's-edge filers

Minimum tax

$50, owed even in a loss year

Multi-state profit

Montana sales over total sales

Annual report

$20 by April 15, $35 after

Estimate your state tax

Pick your business type and enter this year's numbers to see the state business tax Montana charges. It assumes all your sales are in Montana.

An estimate for planning, not tax advice.

Sources

• Montana Form 2 Instructions, 2025
• Montana Form 2, 2025
• sosmt.gov business filing fees schedule ("Annual report prior to April 15th $20.00", "after April 15th $35.00")
• sosmt.gov press releases, 2025 annual report season (fee waiver, 15 April deadline)
• mtrevenue.gov 2025 Montana Form CIT instructions ("The minimum tax that a corporation must pay is $50"; 6.75%; 15 May due date)
• mtrevenue.gov 2025 Montana Form PTE instructions (who must file; 16 March due date; Form PT-AGR; composite tax and PTET elections)
• revenue.mt.gov 2025 Montana Form CIT Instructions: "The tax rate is 6.75 percent with a minimum tax of $50", and "January 1, 2025, Montana uses the Single sales factor method for apportioning income"

Last reviewed August 2026.