Compare taxes and see how much you save moving from Montana to Idaho
Montana and Idaho are two of the Rocky Mountain West's most appealing lifestyle states, and their tax profiles are strikingly similar — but with one key difference. Montana has no sales tax (one of only five US states) while Idaho has a 6% sales tax. On income tax: Montana's top rate is 5.9% (two brackets: 4.7% on $0–$20,500 and 5.9% above) vs Idaho's effectively flat 5.8% — nearly identical. On property tax: Montana ~0.83% vs Idaho ~0.69%; on a $300,000 home, Idaho saves approximately $420/year in property taxes. The sales tax comparison is Montana's major advantage: a family spending $60,000/year on taxable goods saves approximately $2,400/year vs Idaho. Overall: Montana's no-sales-tax benefit often exceeds the modest property tax disadvantage for typical households, making Montana cheaper for most residents who purchase significant goods within the state.
Top Rate (above $20,500)
Two brackets: 4.7% and 5.9%; property tax ~0.83%; no state sales tax
Top Rate (above $4,489 single)
Effectively flat at 5.8% for most workers; property tax ~0.69%; 6% state sales tax
At $100,000 income:
That is $125/month back in your pocket!
| Income | MT Tax | ID Tax | Savings | 10-Year |
|---|---|---|---|---|
| $50,000 | $2,217 MT income tax (~4.43% effective); ~$1,245 property ($150K × 0.83%) = ~$3,462 total; +$0 sales tax | $2,900 ID income tax (5.8%); ~$1,035 property ($150K × 0.69%) = ~$3,935 total; +~$1,500 sales tax on $25K spending | MT saves ~$1,973 including sales tax | $19,730 |
| $75,000 | $3,451 MT income tax (~4.6% effective); ~$1,660 property ($200K × 0.83%) = ~$5,111 total; +$0 sales tax | $4,350 ID income tax; ~$1,380 property ($200K × 0.69%) = ~$5,730 total; +~$2,100 sales tax on $35K spending | MT saves ~$2,719 including sales tax | $27,190 |
| $100,000 | $5,217 MT income tax (~5.22% effective); ~$2,490 property ($300K × 0.83%) = ~$7,707 total; +$0 sales tax | $5,800 ID income tax; ~$2,070 property ($300K × 0.69%) = ~$7,870 total; +~$2,700 sales tax on $45K spending | MT saves ~$2,863 including sales tax; slight MT income+property tax advantage too | $28,630 |
| $150,000 | $8,267 MT income tax (~5.51% effective); ~$3,320 property ($400K × 0.83%) = ~$11,587 total | $8,700 ID income tax; ~$2,760 property ($400K × 0.69%) = ~$11,460 total; +~$3,600 sales tax on $60K spending | MT saves ~$3,473 including sales tax | $34,730 |
| $200,000 | $11,017 MT income tax (~5.51% effective); ~$4,150 property ($500K × 0.83%) = ~$15,167 total | $11,600 ID income tax; ~$3,450 property ($500K × 0.69%) = ~$15,050 total; +~$4,500 sales tax on $75K spending | MT saves ~$4,383 including sales tax | $43,830 |
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Moving between Montana and Idaho? Montana's no-sales-tax vehicle registration strategies, partial-year returns, and Mountain West domicile changes need specialist guidance. Get matched with a CPA who specialises in Western state moves.
⚠ Not for simple single-state returns. Free filing is fine for straightforward W-2 situations.
Get Matched With a CPA →Yes — Montana's lack of sales tax does attract shoppers, particularly for large purchases. Consumers from Idaho, Wyoming, and North Dakota sometimes purchase vehicles, boats, RVs, or high-value electronics in Montana to avoid sales tax. Montana vehicle registrations (Montana LLCs used by non-residents to register vehicles in Montana and avoid their home state's sales tax and registration fees) have been a well-known tax strategy, particularly for luxury cars and motorhomes. Some states have enacted laws to counter this practice, but it remains common. For Montana residents, the no-sales-tax benefit is genuine and permanent — all retail purchases (clothing, electronics, furniture, appliances) are tax-free year-round.
Boise is better for tech employment. Micron Technology's headquarters and largest US fab is in Boise — employing thousands in semiconductor design, manufacturing, and engineering. Hewlett Packard has legacy operations in Boise; several tech and healthcare IT companies (Clearwater Paper, Bodybuilding.com/Liberty Media, Healthwise) maintain Boise operations. Idaho National Laboratory (INL) in Idaho Falls is a major federal research employer accessible to Boise. Bozeman has a growing tech scene driven by Montana State University and remote worker influx, but the formal employer base is far smaller — ski and outdoor industry operations, some tech startups, and Montana State research. For a tech career with employer depth: Boise wins. For lifestyle-first remote workers: Bozeman's appeal is unmatched if affordability is not a constraint.
Montana simplified its income tax from a complex seven-bracket system to two brackets in 2024: 4.7% on taxable income from $0 to $20,500 (adjusted for inflation), and 5.9% on all taxable income above $20,500. The standard deduction is $5,000 for single filers. Montana personal exemption is $2,580. So for a single filer earning $100,000: taxable income approximately $100,000 - $5,000 standard deduction - $2,580 exemption = $92,420; tax = ($20,500 × 4.7%) + ($71,920 × 5.9%) = $963.50 + $4,243.28 = $5,206.78, approximately 5.2% effective rate. Montana's reform (enacted in 2021, taking effect 2024) reduced and simplified from the previous top rate of 6.75%. The 5.9% rate may be further reduced in future sessions.
Montana has a modest advantage for retirees, primarily from the sales tax exemption. For retirees spending $50,000–70,000/year on goods (food, clothing, appliances, vehicle maintenance): Montana saves $3,000–4,200/year in sales taxes. Idaho offers a retirement income deduction of up to $36,500/year per person for filers 65+, significantly reducing Idaho income tax for retirees with pension or IRA income. Both states exempt Social Security benefits from taxation for many income levels. The net comparison depends heavily on spending patterns vs retirement income level. A retiree with $80,000 in retirement income and moderate spending: the Idaho retirement deduction may reduce Idaho income tax to near zero, while Montana's modest income tax and zero sales tax produce a similar total. Consult a CPA for individual situations given the multiple interacting deductions.
Yes — both states offer property tax relief for low-income seniors. Montana's Elderly Homeowner/Renter Credit reduces property tax for filers 62+ with income below $45,000 (approximately) — provides a refundable income tax credit of up to $1,150 for qualifying homeowners. Idaho's Circuit Breaker program provides property tax reduction for homeowners or renters age 65+ (or disabled) with household income below $37,000 (2024 threshold) — reduces property tax owed on the primary residence by up to 90%. Both programs are means-tested and target lower-income seniors. For higher-income retirees (income above these thresholds), the standard property tax rates apply without significant relief. Idaho's lower base property tax rate (0.69% vs Montana's 0.83%) remains an advantage for higher-income retirees not qualifying for circuit breaker benefits.