Carter County Tax Estimator

How property tax works in Carter County

Your bill is the assessed value of your home multiplied by the combined rate of every authority that taxes it — the county, the school district, the city or township, and often a fire or library district. Those rates are set separately and added together, which is why two houses of identical value on opposite sides of a district line can owe different amounts.

Across Carter County, the median home is worth $176,600 and the median property tax bill is $782. Dividing one by the other gives the effective rate of 0.443% used above. That is the honest way to estimate a bill without knowing which districts a specific address falls into.

Income tax in Montana, while you are here

Montana taxes income through 2 brackets, up to 5.65%, on top of the property tax above. Work out your Montana income tax.

Carter County in the national picture

Carter County is in the cheapest tenth of the United States for property tax. Its effective rate of 0.44% sits below 0.46%, the line that separates the bottom 10% of the 3,132 counties we have data for from everyone else. In practical terms, an owner here pays less than half what the median American county charges on the same house.

For scale, the range across the whole country runs from about 0.08% at the bottom to 3.64% at the top. That is a spread of more than twenty to one on the same house, and it is decided almost entirely by where the line on the map falls rather than by anything about the property itself.

What 0.44% costs at each price point in Carter County

The rate is a percentage, so the bill scales straight with the value the assessor puts on the property: $200,000 → $886 a year ($74 a month); $350,000 → $1,550 a year ($129 a month); $500,000 → $2,214 a year ($185 a month); $750,000 → $3,321 a year ($277 a month); $1,000,000 → $4,428 a year ($369 a month).

The median home in Carter County is assessed around $176,600, which is why the typical bill here lands near $782. If you are looking above that price, read the row that matches your budget rather than the median — the median describes the county, not your purchase.

One caveat that catches people out: these figures use assessed value, and in many states that is not the same as the price you paid. Some states assess at a fixed fraction of market value, and some cap how fast an assessment can rise for an existing owner. Both make the published rate look higher or lower than what a specific household actually pays.

What property tax takes out of a Carter County income

Median household income in Carter County is $52,171 and the median property tax bill is $782. That is 1.5% of gross household income going to property tax alone — before any income tax, before FICA, and before the mortgage the tax sits on top of.

At 1.5% this is a manageable share by national standards, but note what it is measured against: median income, not your income. A retiree on a fixed income in the same house pays the same bill as the household earning $52,171, which is why almost every state has some form of senior or disability relief and why it is worth asking the assessor whether you qualify.

This is also the number that rent quietly reflects. A landlord in Carter County pays the same $782 on a comparable property and prices it into the lease, so the tax reaches renters too — it just arrives without a bill attached.

Why Montana counties charge such different rates

Property tax is set locally, so Montana does not have one rate — it has 56. They run from 0.41% in Madison County to 1.52% in Blaine County, with Carter County at 0.44%, 2nd cheapest of 56.

That is a spread of more than 3.7 to one inside a single state, which tells you the state rules are not what is driving the number. What drives it is the local mix: how much of the school budget comes from the state rather than the district, whether there is commercial or industrial value to spread the burden across, and how fast home values have moved relative to the budgets those values have to fund.

The practical consequence is that a rate you were quoted for Montana as a whole is close to meaningless. The number that applies to you is the one for your county, and often for your district within it.

Property tax and income tax in Montana, together

Montana taxes income as well as property, so a full picture of what living in Carter County costs needs both. The property side is local and is on this page; the income side is set at state level and applies wherever in Montana you live.

The two are worth adding together rather than comparing separately, because states trade them off against each other. A state with a low income tax often leans harder on property, and vice versa — which is why a single-tax comparison between two states can point the wrong way.

What the Carter County figure is, and what it is not

The 0.44% on this page is an effective rate: the Census Bureau's median property tax paid in Carter County ($782) divided by its median home value ($176,600), both from the American Community Survey five-year estimates. It is a real, citable measure of what owners here actually pay.

It is not a millage rate, and it is not the number on your tax bill. Your bill is the sum of every levy that reaches your parcel — county, school district, city or township, and often a fire, library or water district — applied to your assessed value after any exemption you qualify for. Two houses of the same value on opposite sides of a district line in Carter County can owe different amounts, and both are correct.

Use this figure to compare Carter County against other places and to sanity-check an escrow estimate. Use the assessor's roll to find out what you owe.

Carter County at a glance

Carter County has a population of about 1,361, 799 housing units, and a median household income of $52,171.

It is a small county, and that has two consequences for the numbers here. Census estimates carry wider margins of error on small populations, and a single large taxpayer — a plant, a utility, a resort — can move the whole rate when it arrives or leaves.

The Montana rules that change your Carter County bill

Montana’s reform does not exempt value — it gives your home a LOWER TAX RATE. HB 231 of 2025 created the Homestead Rate for principal residences and long-term rentals, tiered so each slice of market value is taxed at its own rate rather than the whole at one. The state projects a 15% cut for homeowners and 18% for small businesses.

Montana determines 100% of market value and then applies a class tax rate to get taxable value — residential is class four. Reappraisal runs on a TWO-year cycle for residential property, among the shortest in the country, so Montana values track the market closely and move in visible steps.

You must occupy the home for at least seven months a year, and ownership must be individual, joint or through a grantor revocable trust — an LLC, partnership, corporation or irrevocable trust is disqualified outright. Applications have a hard deadline, and missing it means paying the higher rate for the year.

These are Montana rules and they apply in every county in the state, Carter County included. What varies locally is the rate, not the relief — so if you qualify for the relief and have not claimed it, the Carter County assessor is where that gets fixed.

The ten-year figure, which is the one that decides a purchase

A single year's property tax is a number people accept without much thought. The decade is the number that changes decisions, because unlike a mortgage it never amortises away and unlike income tax it does not fall when your income does.

On Carter County's median home value of $176,600, held ten years with assessed value rising 4% a year, Carter County collects about $9,389. The cheapest county in the state collects $8,663 over the same period and the dearest $32,271 — a spread of $23,607 on identical property, decided entirely by location.

The same house at the national median rate of 0.84% would run $17,749 over ten years, so Carter County costs about $8,360 less across the decade than a typical American county would.

Set that against the mortgage to see the weight of it. On a $176,600 purchase the ten-year property tax bill in Carter County is roughly 7% of the amount financed at 80% loan-to-value — before insurance, before maintenance, and before any millage increase. It is the largest recurring cost of ownership after interest, and the only one that a district can raise without asking you.

A rate in the national bottom decile makes this the smallest of the recurring ownership costs, below insurance in many years. The trap that creates is complacency about the base: where the tax is low, owners rarely scrutinise the assessment, and a reassessment after a long gap arrives as several years of market movement at once with no habit of challenging it.

Appealing a Carter County assessment: what it is worth

You cannot appeal the tax rate — that is set by budget votes you have no standing to challenge individually. What you can appeal is the assessor's opinion of your property's value, and that is a factual claim you can be right or wrong about.

The arithmetic decides whether it is worth your afternoon. On the median home in Carter County, $176,600, the bill runs about $782 a year. A 10% reduction in assessed value is worth roughly $78 a year, and because the corrected value carries forward it is nearer $391 across five years. Under $60 a year, the paperwork rarely pays; over $400, it usually does.

At this size a formal challenge is rarely worth the afternoon, and the better use of the same effort is the record itself: a factual correction costs one phone call and is usually granted without a hearing. Save the comparable-sales route for a year in which the valuation moves sharply, which in a lower-value area typically follows a reassessment cycle rather than arriving annually.

Also check the record itself before arguing valuation, because errors are commoner than contested opinions: square footage that includes an unfinished basement, a bathroom that does not exist, a garage counted twice, land area from a survey predating a lot split. A factual correction is usually granted without a hearing.

The deadline in Montana: There is a hard application deadline for the Homestead Rate, and missing it means paying the higher rate for the whole year. Miss it and there is generally no remedy until the following cycle, whatever the merits — property tax appeal windows are short and strictly applied, and they typically start from the date the notice was mailed rather than the date you opened it.

How the bill is paid, and what happens if it is not

Most owners with a mortgage never pay this directly. The servicer collects roughly $65 a month alongside principal and interest on the median Carter County bill, holds it in escrow, and pays the county when it falls due. The consequence is that a rise reaches you as a change in your monthly payment months after the fact, with no obvious connection to the assessment notice that caused it.

Read the annual escrow analysis when it arrives. It shows the bill actually paid, and it is the cheapest way to catch an assessment you would have appealed had you noticed — by the time the payment changes, the appeal window for that year has usually closed.

The weight here is light: the median bill is 1.50% of median household income, so escrow rarely drives a purchasing decision and an increase is absorbed rather than felt. The consequence worth knowing is the reverse of the usual complaint — where the tax is small relative to income, owners tend not to open the assessment notice at all, and unclaimed exemptions go unnoticed for years.

Unpaid property tax is also secured against the house itself, which is what separates it from every other tax. States permit a tax lien, and eventually a tax sale, at the end of a statutory redemption period. It is slow and heavily noticed, so it is nearly always avoidable — but the mechanism means an unpaid property tax bill can never simply be written off the way an unpaid income tax debt sometimes is.

The Montana counties either side of Carter County

The Montana county immediately cheaper than Carter County: Madison County at 0.41%. On a $400,000 home the move from Carter County to Madison County would save about $137 a year.

Immediately more expensive: Judith Basin County at 0.45%, Sweet Grass County at 0.49%, Golden Valley County at 0.51%. If you are weighing Carter County against Judith Basin County, the rate gap on a $400,000 home is about $42 a year — worth knowing, but rarely the largest difference between two places.

Comparisons like these are the reason to use an effective rate rather than a millage. Millage rates are not comparable across county lines because assessment practices differ; tax paid over value paid is.

What actually sets your Carter County bill

Three numbers decide your bill, and the rate is only one of them. The first is assessed value, and Montana taxes the full market value rather than a fraction of it — so nothing is discounted before the exemptions come off, and the headline rate here means what it says.

The second is how fast that value is allowed to move. We have not loaded a statewide cap for Montana, so assume your assessment can follow the market unless your assessor tells you otherwise.

The third is the combined rate of every authority that reaches your parcel — the county, the school district, the city or township, often a fire or library district. They are set separately and added, which is why two houses of identical value on opposite sides of a line in Carter County owe different amounts and both figures are correct.

Buying in Carter County? Read this first

Property tax is the part of the monthly cost buyers most often underestimate, because it does not surface until the lender builds the escrow. On a $400,000 home in Carter County it adds roughly $148 a month on top of principal, interest and insurance — $1,771 a year.

One rule to check before you rely on the seller's number: whether Montana revalues the property when it changes hands. Where it does, the seller's bill can understate yours badly; where it does not, you inherit their position. We have not loaded that rule for Montana, so ask the Carter County assessor directly rather than assuming.

Then ask what relief you qualify for in your first year. There is a hard application deadline for the Homestead Rate, and missing it means paying the higher rate for the whole year. Relief that is not claimed is not given.

If your Carter County assessment looks wrong

You can contest the assessed value. You cannot contest the rate — that is set by elected bodies and is not open to appeal. So the question to answer before filing is narrow: would this property actually sell for what the assessor says it is worth?

Gather comparable sales close to the assessment date rather than to today. An assessor is defending a valuation as of a particular day, and recent sales that postdate it carry little weight.

There is a hard application deadline for the Homestead Rate, and missing it means paying the higher rate for the whole year. The Carter County assessor's office is where the clock is published, and missing it costs the whole year — there is no late appeal in most jurisdictions.

Carter County property tax questions

How much is property tax in Carter County?

The effective rate in Carter County is 0.44%, from a median tax bill of $782 on a median home value of $176,600. On a $400,000 home that is about $1,771 a year, or $148 a month once it is in escrow.

Is property tax high in Carter County?

No, the opposite: Carter County is in the cheapest tenth of the United States at 0.44%, against a national median of 0.84%.

Which Montana county has the lowest property tax?

Madison County at 0.41%, with Blaine County the most expensive at 1.52%. Carter County sits at 0.44%, 2nd cheapest of the 56 Montana counties with published data.

Will my Carter County tax bill change when I buy?

That depends on whether Montana revalues a property when it changes hands, and we have not loaded that rule for Montana. It matters: in states that reassess on sale, the seller's bill can badly understate what you will pay. Ask the Carter County assessor before you rely on the current figure.

Is there a homestead exemption in Carter County?

Not in the usual form. Montana’s reform does not exempt value — it gives your home a LOWER TAX RATE. HB 231 of 2025 created the Homestead Rate for principal residences and long-term rentals, tiered so each slice of market value is taxed at its own rate rather than the whole at one. The state projects a 15% cut for homeowners and 18% for small businesses.

Do seniors pay property tax in Carter County?

You must occupy the home for at least seven months a year, and ownership must be individual, joint or through a grantor revocable trust — an LLC, partnership, corporation or irrevocable trust is disqualified outright. Applications have a hard deadline, and missing it means paying the higher rate for the year. That is a Montana rule and it reaches Carter County like every other county in the state; the Carter County assessor or treasurer handles the application.

Is my Carter County home taxed on its full market value?

Yes. Montana determines 100% of market value and then applies a class tax rate to get taxable value — residential is class four. Reappraisal runs on a TWO-year cycle for residential property, among the shortest in the country, so Montana values track the market closely and move in visible steps. That is worth knowing when you compare Montana against a state that taxes a fraction — a lower rate somewhere else can still mean a higher bill.

Can I appeal my Carter County assessment?

You can contest the assessed value, but not the rate — the rate is set by elected bodies and is not open to appeal. There is a hard application deadline for the Homestead Rate, and missing it means paying the higher rate for the whole year. The Carter County assessor's office publishes the current window, and in most jurisdictions there is no late appeal.

Does Montana have an income tax as well?

Yes. Montana taxes income at graduated rates up to 5.65%, on top of the property tax on this page. Worth adding the two together before comparing Montana against anywhere else.

Do I need a parcel number to use this calculator?

No, and that is deliberate. The Carter County assessor's own estimator generally asks for one, which is fine if you already own the property and useless if you are deciding whether to buy it. This works from the home value instead. It is an estimate built on the county's effective rate, which averages across every district inside Carter County, so your exact bill depends on your district combination and on any exemption you qualify for. For the binding figure, the Carter County assessor or treasurer is the authority.