A Montana property tax bill arrives once a year from your county treasurer and is paid in two installments: the first half by November 30 and the second half by May 31 of the following year. The bill shows your property’s market value, the taxable value after Montana’s class-based rate is applied, the combined mill levy from every taxing jurisdiction you sit in, and the dollar total you owe. Relief programs can lower that total if you qualify, and you can challenge the assessed value if it looks wrong.
Reading Your Bill
Two numbers near the top do most of the work. Market value is the Department of Revenue’s estimate of what your property would sell for. Taxable value is a much smaller figure produced by applying a tax rate percentage, set by your property’s classification, to that market value.1Montana State Legislature. Property Tax Overview
The mill levy is the tax rate expressed per $1,000 of taxable value. One mill equals $1 per $1,000. The total mill levy on your bill is the sum of levies from every jurisdiction covering your parcel: state, county, school district, city, fire district, and any special districts.1Montana State Legislature. Property Tax Overview
You’ll also see a 17-digit Geocode the Department of Revenue uses to identify your parcel. Confirm it matches your property before paying, particularly if you own more than one. Below the main tax amount, separate line items may appear for special assessments that fund things like street lighting, weed control, or rural improvement districts. These are flat charges, not value-based, and are billed alongside your regular taxes.
How the Amount Is Calculated
Montana sorts property into numbered classes and gives each class a tax rate. That rate turns market value into taxable value, and taxable value times the combined mill levy produces your bill. Most homeowners fall under Class 4 residential.
Primary Residences and Long-Term Rentals
Starting with tax year 2025, Montana applies a tiered rate to primary residences and qualifying long-term rentals. For 2026, the tiers run off the statewide median residential value of $378,000:2Montana Department of Revenue. 2026 Tax Information for Montana Property Owners
- First $378,000 of market value: 0.76%
- $378,001 to $756,000: 0.90%
- $756,001 to $1,511,999: 1.10%
- $1,512,000 and above: 1.90%
Second Homes and Short-Term Rentals
Residential property that doesn’t qualify as a primary residence or long-term rental is taxed at a flat 1.90% of the entire market value.3Montana Code Annotated. Montana Code 15-6-134 – Class Four Property – Description – Taxable Percentage The gap is large. A $400,000 home used as a primary residence produces far less taxable value than the same home run as a vacation rental.
Agricultural Land
Qualified agricultural land is taxed at 2.05% of its agricultural productivity value, not its market value. A home sitting on agricultural land still uses the Class 4 tiered rates if it’s a primary residence or long-term rental, and 1.35% if it’s a second home or short-term rental.2Montana Department of Revenue. 2026 Tax Information for Montana Property Owners
Deadlines, Penalties, and Interest
The first installment is due by 5:00 p.m. on November 30, and the second by 5:00 p.m. on May 31. If your tax notice was mailed late, you get 30 days from the postmark on the notice, and that date replaces November 30 if it falls later. When a deadline lands on a Saturday or legal holiday, you have until 5:00 p.m. the next business day.4Montana Code Annotated. Montana Code 15-16-102 – Time for Payment – Penalty for Delinquency
Miss either deadline and the delinquent amount takes a flat 2% penalty, plus interest at 5/6 of 1% per month (about 10% per year) accruing from the day of delinquency until you pay in full.4Montana Code Annotated. Montana Code 15-16-102 – Time for Payment – Penalty for Delinquency On a $3,000 installment, that’s $60 in penalty on day one and roughly $25 per month in interest.
A missing bill does not extend your deadline. If yours never arrived or you misplaced it, contact the county treasurer or check their website. You still owe on time.
If Your Mortgage Pays It
Most homeowners with a mortgage never deal with these deadlines directly. A portion of each monthly payment goes into escrow, and the lender sends the full tax payment to the county on your behalf.5Montana State Legislature. HJ 36 Monthly Property Tax Payments Lenders pay on time because an unpaid tax lien outranks their mortgage.
Still look at the annual bill when it arrives. If your assessed value jumped, escrow needs to grow with it, and some lenders are slow to adjust. A shortfall can turn into a lump-sum catch-up charge or higher monthly payments mid-year.
Paying Directly
If you pay the county yourself, you have three options. Mailed payments must be postmarked by the deadline. Most counties take online payments through the treasurer’s website, usually by credit card or e-check. Credit card convenience fees typically run 2.5% to 3% of the payment; e-check fees are usually a small flat amount. In-person payment at the county treasurer’s office gets you a receipt on the spot.
You’ll need the Geocode or property tax ID from your bill. If you mail a check, write that number on the memo line so the treasurer can match the payment if the stub gets separated. Keep your receipt or confirmation number.
Relief Programs
Montana runs several programs that can meaningfully cut your bill, and all of them require an application. Nothing is automatic.
Property Tax Assistance Program (PTAP)
PTAP reduces the taxable value of your home if your income is limited. You must own and occupy the home as your primary residence for at least seven months of the year. Eligibility runs off your 2024 federal adjusted gross income, the benefit applies only to the first $418,000 of market value, and the application deadline is April 15.6Montana Department of Revenue. Property Tax Assistance Program (PTAP)
For 2026, single filers qualify at:
- $0 to $14,286: 80% reduction in taxable value
- $14,287 to $19,532: 50% reduction
- $19,533 to $29,037: 30% reduction
Married filers and heads of household qualify at:
- $0 to $19,249: 80% reduction
- $19,250 to $29,085: 50% reduction
- $29,086 to $38,917: 30% reduction
An 80% reduction can take hundreds or thousands of dollars off an annual bill, depending on the property’s value and local levies.6Montana Department of Revenue. Property Tax Assistance Program (PTAP)
Montana Disabled Veteran Assistance Program
Veterans rated 100% disabled by the U.S. Department of Veterans Affairs, and their unmarried surviving spouses, qualify for property tax reductions of 50% to 100% depending on income.7Montana Code Annotated. Montana Code 15-6-311 – Disabled Veteran Program For 2026, a single filer with income up to $48,152 gets the full 100% reduction, and a married filer up to $57,781. Surviving spouses have separate, slightly lower thresholds.8Montana Department of Revenue. Montana Disabled Veteran Assistance Program
Elderly Homeowner and Renter Credit
If you’re 62 or older, lived in Montana for at least nine months of the year, and have gross household income below $45,000, you can claim up to $1,150 on your state income tax return. It applies whether you own or rent, as long as you occupied an eligible dwelling for at least six months.9Montana State Legislature. Elderly Homeowner and Renter Credit You claim this one through your income tax filing, not through a separate property tax application.
Appealing the Assessed Value
If your market value looks too high, you can challenge it. Successful appeals usually show the Department of Revenue worked from incorrect information: wrong square footage, a condition issue they missed, or comparable sales that don’t fit your neighborhood.
Start with Form AB-26, filed with your local Department of Revenue field office within 30 days of the date on your classification and appraisal notice. That triggers an informal review where a department appraiser looks at your evidence and may adjust the value without a hearing. Most disputes end here.
If the informal review doesn’t resolve it, appeal to your county tax appeal board within 30 days of the department’s decision.10Montana Tax Appeal Board. Appeal Process You or your agent must attend the county hearing. If the county board refuses or fails to hear a timely application, the law treats your requested value as granted.11Montana Code Annotated. Montana Code 15-15-103 – Examination of Applicant – Failure to Hear Application After the county board, you can take the matter to the state-level Montana Tax Appeal Board. If you plan to submit a private appraisal, it should reflect the statutory valuation date, not the date you ordered it.12Montana Tax Appeal Board. Procedures and Suggestions for Property Tax Appeals
What Happens If You Don’t Pay
Taxes become delinquent the day after a missed deadline, and the 2% penalty plus monthly interest start accruing right away.4Montana Code Annotated. Montana Code 15-16-102 – Time for Payment – Penalty for Delinquency
If taxes stay unpaid through the summer, the county treasurer must attach a tax lien to the property no later than the first working day of August. Before doing so, the county mails notice to the owner’s last known address at least two weeks in advance. Once attached, the lien is filed in the public record with the county clerk and recorder.
After the lien is in place, a third party can purchase the assignment of that lien from the county and must send the owner a certified-mail notice before completing the purchase. The owner then has a 36-month redemption period from the date of the tax lien sale to pay all delinquent taxes, penalties, interest, and costs. If that window closes without payment, the lien holder can apply for a tax deed and take ownership. For vacant subdivided lots with unpaid special improvement assessments, the redemption period is 24 months.