Selling a business in Montana: what the state takes (2026)
Montana’s top individual income tax rate is 5.65%. Here is what an owner selling company stock pays, with 2026 rules from official sources and worked examples at $10 million, $25 million and $50 million.
- 5.65%
- Top Montana income tax rate (2026)
- $1,025,000
- State tax on a $25M long-term gain
- 27.9%
- Combined federal and state rate on $25M
- 29 of 51
- Rank by total tax on $25M (1 = highest)
How Montana taxes a business sale
- Income tax
- Top rate 5.65%: Ordinary income over $47,500 (single), 2026; falls to 5.4% over $65,000 in 2027. Long-term capital gains are taxed on a separate 3.0%/4.1% schedule..
- Long-term capital gains
- Net long-term capital gains are taxed on a separate lower schedule: 3.0% on the first $47,500 (single, 2026) less other taxable income, and 4.1% above that. On a gain of $10M or more effectively the whole gain is taxed at 4.1%. The former 2% capital gains credit (MCA 15-30-2301) was repealed by Ch. 503, L. 2021.
Three worked examples
| Long-term gain | $10,000,000 | $25,000,000 | $50,000,000 |
|---|---|---|---|
| Federal capital gains tax (20%) | $2,000,000 | $5,000,000 | $10,000,000 |
| Net investment income tax (3.8%) | $380,000 | $950,000 | $1,900,000 |
| Montana tax | $410,000 | $1,025,000 | $2,050,000 |
| Total tax | $2,790,000 | $6,975,000 | $13,950,000 |
| Effective combined rate | 27.90% | 27.90% | 27.90% |
| Net proceeds after tax | $7,210,000 | $18,025,000 | $36,050,000 |
| Extra tax versus Texas | $410,000 | $1,025,000 | $2,050,000 |
Seller’s tax calculator
Estimate federal and state tax on a stock sale and what is left before fees and debt.
- Long-term capital gain
- $25,000,000
- Federal capital gains tax (20%)
- $5,000,000
- Net investment income tax (3.8%)
- $950,000
- Montana tax
- $1,025,000
- Taxable gain at 4.1%
- $1,025,000
- Total tax
- $6,975,000
- Effective rate on the gain
- 27.90%
- Net proceeds after tax
- $18,025,000
Illustration, not tax advice. Assumes a resident individual, the whole gain long-term, top marginal rates, no state credits, installment terms, QSBS exclusion or other planning, and no local taxes. Net proceeds are before transaction fees, debt repayment, escrows and earn-outs. Rates are for tax year 2026 where published; see the methodology.
Compare with other states
Neighboring states
- Idaho29.1% combined, $17.73M net
- North Dakota25.3% combined, $18.68M net
- South Dakota23.8% combined, $19.05M net
- Wyoming23.8% combined, $19.05M net
Common comparisons
- California37.1% combined, $15.72M net
- New York34.1% combined, $16.48M net
- Texas23.8% combined, $19.05M net
- Florida23.8% combined, $19.05M net
- Nevada23.8% combined, $19.05M net
- Washington33.5% combined, $16.63M net
- Tennessee23.8% combined, $19.05M net
Methodology and sources
Montana figures are for tax year 2026. 2026 rates set by HB 337 (Ch. 227, L. 2025) and codified in MCA 2025 15-30-2103 as a temporary version ending Dec 31, 2026; the department's 2026 rate table PDF was not retrievable (404), so statute and DOR's HB 337 notice were used. The examples assume a resident individual selling privately held stock for a long-term gain equal to the sale price (zero basis), with every dollar taxed at the top marginal rates, the federal 20% capital gains rate and the 3.8% net investment income tax, and no planning, credits or local taxes. Full assumptions are in the report methodology.
All 50 states and DC with source URLs.
- 1MCA 2025 15-30-2103, rate of tax: net long-term capital gains (temporary 2026 version and 2027 version)
- 2Montana DOR, HB 337 individual income tax changes
- 3MCA 15-30-2301 capital gain credit (repealed, Ch. 503, L. 2021)
- 4Tax Foundation, State Individual Income Tax Rates and Brackets, 2026 (as of Feb 11, 2026). Secondary source
Data last updated October 26, 2026.
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Citation
Laurent Capital Research, “The Seller’s Tax Map: What Selling a Business Costs in Every State (2026): Montana,” 2026, https://laurent.capital/research/seller-tax-map/montanaLink (HTML)
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