Montana state income tax calculator

Estimate Montana income tax using the 4.7%/5.9% bracket schedule.

How this calculator works

Step 1 starts with the Montana taxable income you already calculated on your return. If you are a part-year resident or nonresident, the tool applies the Montana income percentage you provide to focus on Montana-source income.

Step 2 applies Montana's two-bracket schedule (4.7% up to the filing-status threshold and 5.9% above) to estimate total tax.

Step 3 summarizes the effective and marginal rates so you can see how additional income would be taxed and whether your current estimate matches your expectations.

Frequently asked questions

What income should I enter?

Use Montana taxable income from your return. If you only know total income, estimate deductions first or use the standard deduction tool.

Do part-year residents prorate income?

Yes. Use the Montana income allocation percentage from your return to prorate taxable income before applying the Montana bracket schedule.

Does Montana have different brackets by filing status?

Yes. The 4.7% bracket ends at $21,100 single/$21,100 married separate, $31,700 head of family, and $42,200 married filing jointly. Income above those thresholds is taxed at 5.9%.

Is this tax advice?

No. This tool provides estimates based on the inputs you provide and is not legal or tax advice.

This tool provides estimates based on Montana's published brackets (4.7%/5.9%). Not legal or tax advice.