Montana State Tax Calculator 2026
Estimate your Montana state income tax and take-home pay for tax year 2026.
Last updated: November 2025 · Source
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Montana 2026 tax overview
HB337 effective 2026: 2 brackets, top rate cut from 5.9% to 5.65%. Further cut to 5.4% in 2027.
Breakdown
Montana income tax brackets, 2026
Rates apply to each slice of taxable income in turn, not to the whole amount. Reaching the 5.65% bracket does not mean paying 5.65% on everything. Figures are for single filers unless the state uses one schedule for all statuses.
| Taxable income | Rate | Tax on this bracket |
|---|---|---|
| $0 to $47,500 | 4.70% | $2,233 max |
| Over $47,500 | 5.65% | 5.65% of everything above $47,500 |
Montana conforms to the federal standard deduction: $16,100 single, $32,200 married filing jointly for 2026.
Frequently Asked Questions
What are the 2026 Montana income tax rates?
Montana uses a 2-bracket progressive schedule for 2026, running from 4.70% to 5.65%. The top rate starts at $47,500 of taxable income. HB337 effective 2026: 2 brackets, top rate cut from 5.9% to 5.65%. Further cut to 5.4% in 2027.
At what income does the top Montana tax rate start?
The 5.65% top rate applies to taxable income above $47,500. Below that, 1 lower brackets apply in sequence, so your average rate is always lower than your top rate.
What is the 2026 Montana standard deduction?
Montana conforms to the federal standard deduction, which is $16,100 single and $32,200 married filing jointly for 2026 under IRS Rev. Proc. 2025-32.
Does Montana have tax reciprocity with neighbouring states?
Yes. Montana has reciprocal agreements with North Dakota. If you live in one of those states and work in Montana, you file and pay only where you live, and you give your employer the relevant non-residence certificate so Montana tax is not withheld. Without that form the tax is withheld anyway and you have to file a Montana return to get it back.
Does Montana tax Social Security and retirement income?
Montana is one of the eight states that still tax Social Security, and it follows the federal taxable amount. Filers 65 and over get an additional exemption.
What surprises people most about Montana income tax?
Montana has no sales tax at all, which is the trade-off for taxing a broader base of income.