Montana capital gains tax (2026)
West · Special rate 4.1% · combined top long-term 27.9%
In Montana, the effective top rate on long-term capital gains is about 4.1%. Added to the federal top long-term rate of 23.8% (20% plus the 3.8% NIIT), the illustrative combined top long-term rate is 27.9% - ranking #28 of 51 states. Ordinary income tops out at 5.65%, but net long-term capital gains are taxed at reduced rates of 3.0% or 4.1% depending on income. This is the top-bracket case, not what a typical filer pays, and not tax advice.
Source: Tax Foundation, 2026 state income tax rates. Data as of June 2026.
How Montana taxes capital gains
Ordinary income tops out at 5.65%, but net long-term capital gains are taxed at reduced rates of 3.0% or 4.1% depending on income.
| Component | Rate |
|---|---|
| Federal long-term rate (top) | 20% |
| Net Investment Income Tax (NIIT) | 3.8% |
| Federal subtotal (top long-term) | 23.8% |
| Montana effective top long-term rate | 4.1% |
| Combined top long-term rate | 27.9% |
Source: Tax Foundation, 2026 state income tax rates. Data as of June 2026.
The federal subtotal of 23.8% applies only to top-bracket long-term gains; lower-income filers pay 0% or 15% federally. The Montana figure is the effective top long-term rate.
Worked example
On a $100,000 long-term gain for a top-bracket investor in Montana: the state takes roughly 4.1% (about $4,100), federal long-term tax is $20,000, and the 3.8% NIIT adds $3,800 - a combined estimate near $27,900, an effective rate close to 27.9%. Lower-income filers pay less federally (15% or 0%).
Estimate only. Use the calculator with your own numbers.
How Montana ranks
| Measure | Montana | Rank (1 = highest) |
|---|---|---|
| Combined top long-term rate | 27.9% | #28 of 51 |
| State effective top long-term rate | 4.1% |
States with a similar capital gains burden
| State | State treatment | Combined top long-term rate |
|---|---|---|
| Montana (this state) | Special rate 4.1% | 27.9% |
| Mississippi | Taxed as ordinary income | 27.8% |
| North Carolina | Taxed as ordinary income | 27.79% |
| Michigan | Taxed as ordinary income | 28.05% |
| Iowa | Taxed as ordinary income | 27.6% |
| Colorado | Taxed as ordinary income | 28.2% |
Frequently asked questions
Does Montana tax capital gains?
Yes. Ordinary income tops out at 5.65%, but net long-term capital gains are taxed at reduced rates of 3.0% or 4.1% depending on income. On top of the state tax you also owe federal capital gains tax (0/15/20% long-term) and, for higher earners, the 3.8% NIIT.
What is the capital gains tax rate in Montana in 2026?
Montana's effective top rate on long-term capital gains is about 4.1%. Combined with the top federal long-term rate of 23.8%, the illustrative combined top rate is 27.9% - the top-bracket case, not what most filers pay.
How does Montana compare with other states on capital gains?
On the illustrative combined top long-term rate, Montana ranks #28 of 51 (1 = highest). States are compared on their effective top long-term rate plus the federal 23.8% top. See the rankings for the full picture.
Are short-term capital gains taxed differently in Montana?
Generally short-term gains are taxed as ordinary Montana income (the headline rate), while any state preferential rate or exclusion usually applies only to long-term gains. Federally, short-term gains are ordinary income (up to 37%).
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Sources & accuracy
Montana treatment from Tax Foundation, 2026 state income tax rates and the state revenue department (find Montana's tax authority). Federal figures from the IRS. Data as of June 2026 for the 2026 tax year. Rates change and special rules have conditions - this is general information, not tax advice. Verify with the official source or a tax professional. See our methodology and disclaimer.
Last updated: 2026-06-21