Property tax estimator, county by county

Why this is a county question

Income tax is set by your state. Property tax is not — it is the sum of every authority that reaches your parcel: the county, the school district, the city or township, often a fire or library district. They set their rates separately and add them together, which is why two houses of identical value on opposite sides of a district line owe different amounts and both figures are correct.

The scale of the difference is the thing most people underestimate. Across the 3,132 counties with published data, effective rates run from 0.08% to 3.64%. On a $400,000 home that is a difference of tens of thousands of dollars over a decade, decided almost entirely by where the line on the map falls.

3,132 counties, and why the state average is useless

Property tax is set locally, so the meaningful unit is the county and not the state. Across the 3,132 counties with published data, effective rates run from 0.08% to 3.64%, with a median of 0.84%. The middle eighty percent falls between 0.46% and 1.57%.

On a $400,000 home those percentiles are $1,828 and $6,274 a year — a difference of $4,446 annually, $44,456 over a decade, on the same house. That is the cost of the county line, and it is larger than most buyers' entire moving budget.

State averages hide this because the variation is mostly within states rather than between them. Several states contain counties on both sides of the national median, so the state figure describes no actual place in it. A state average is an average of things that do not resemble each other.

The rates here are effective rates: median tax actually paid in a county divided by its median home value, from the Census American Community Survey. They already contain the assessment ratio, the exemptions people actually claimed, and every overlapping district — which is what makes them comparable across state lines when a millage rate is not.

Property tax runs backwards from every other tax

Income tax starts with a rate and produces revenue. Property tax starts with the revenue a district needs, divides it by the total assessed value in the district, and the rate is whatever falls out of that division. Nobody sets the rate; it is a quotient, and understanding that explains almost every confusing thing about a property tax bill.

It is why your bill can rise while the rate falls. If assessed values across a district climb faster than its budget, the rate must drop to collect the same money — and the owner whose property gained the most value still pays more than last year. It is also why a district that loses its largest employer sees rates rise with no vote and no new spending.

It is why identical houses on the same street pay differently: your bill is the sum of every authority reaching your parcel — county, school district, city or township, and often fire, library or water districts — each setting its own rate. A district boundary running down a street is enough.

And it is why the poorest districts often have the highest rates. Where a state funds most of education centrally, local rates converge; where districts raise it themselves, the district with the smallest tax base needs the highest rate to fund the same school. Commercial, industrial and utility value is what spreads the load away from houses, and its absence is the usual explanation for a county at the top of a state's range.

Market value, assessed value, and why we publish effective rates

Three different numbers get called "your home's value" and only one of them is taxed. Market value is what it would sell for. Assessed value is what the assessor records, which in many states is a fixed fraction of market value. Taxable value is the assessed value after exemptions — and the millage applies to that.

This is why millage rates cannot be compared across state lines. A 3% millage on 40% of market value and a 1.2% millage on full market value produce the same bill, and a table listing both as published makes the first look nearly three times worse. Of the 51 jurisdictions whose rules we have loaded, assessment practice varies enough that no single conversion applies.

So every rate on this site is an effective rate: median tax actually paid divided by median home value, from the Census American Community Survey. It already contains the assessment ratio, the millage of every overlapping district, and the exemptions residents actually claimed. It is the only figure that survives comparison between a county in one state and a county in another.

Reassessment cycles explain the other common shock. States reassess annually, on a multi-year cycle, or only on sale. Where it is infrequent, the correction when it finally lands is not a rate increase — it is several years of market movement arriving at once, and appealing the rate rather than the valuation is arguing the wrong point in the wrong forum.

Homesteads, caps, and the distinction that costs people money

Of the 51 states and the District of Columbia, 30 have a homestead exemption we have loaded from the state's own publication, 16 limit growth in some form, and 41 publish specific relief for older owners. 51 of the 51 sets of rules have been read off a primary source rather than a compilation.

The caps are where comparisons go wrong, because three different things are all called a cap. 10 states cap the assessed VALUE — California's Proposition 13 at 2% a year, Texas at 10%. 3 cap the BILL, so the assessment may climb but the charge may not. 3 cap the LEVY: how much more the district as a whole may collect, which limits neither your assessment nor your bill.

That last one is the trap. Telling a Washington homeowner their assessment cannot rise more than 1% is simply false — the 1% limits what the district collects in total, and if your property gained value faster than your neighbours' the fixed pot is redistributed toward you. Your bill can rise well beyond the cap while the cap is being honoured exactly.

Exemptions have their own trap, and it is more expensive: in most states they are not automatic. A homestead exemption attaches to a primary residence and generally must be claimed once after purchase, with nothing on the bill to announce that it is missing. It also lapses — on conversion to a rental, on moving out, on inheriting without re-filing — and where a cap is tied to homestead status, losing the status releases the cap too.

Appealing an assessment: what it is worth and what wins

You cannot appeal a tax rate — it comes from budget votes you have no individual standing to challenge. You can appeal the assessor's opinion of what your property is worth, and that is a factual claim that can be right or wrong. Almost every successful challenge is about value, not about the size of the bill.

The arithmetic decides whether it is worth the afternoon. On a $400,000 home at the national median rate of 0.84%, the bill is about $3,348 a year, so a 10% reduction in assessed value is worth roughly $335 a year — and because the corrected value carries forward, nearer $1,674 over five years. In a county at the ninetieth percentile the same reduction is worth $627 a year.

What wins is comparable sales: three to five recent arm's-length transactions in genuinely similar properties, near the valuation date. What loses is what the bill does to your budget, what the previous owner paid, or that the rate went up — none of those speak to value, which is the only question the board is deciding.

Check the record before arguing valuation at all, because factual errors are commoner than contested opinions and are usually corrected without a hearing: square footage counting an unfinished basement, a bathroom that does not exist, a garage counted twice, land area from a survey predating a lot split.

Deadlines are short, locally set, and strictly applied — commonly thirty to forty-five days from the date the notice was mailed rather than the date you read it. Missing the window generally forfeits the year however strong the case was, which is why the assessment notice is worth opening the day it arrives. Each state page here carries its own deadline where the state publishes one.

Escrow, arrears, and who actually bears the tax

Most owners with a mortgage never pay this bill directly. The servicer collects roughly $279 a month alongside principal and interest on a median-rate $400,000 home, holds it in escrow, and pays the county when it falls due. The consequence is that an increase reaches you as a changed monthly payment months later, with no visible connection to the assessment notice that caused it.

Read the annual escrow analysis when it arrives — it names the bill actually paid, and it is the cheapest way to catch an assessment you would have appealed. By the time the payment changes, that year's appeal window has usually closed.

Owners without a mortgage pay the county directly, generally in two instalments, and late payment carries statutory interest that is not small: rates around 1% a month are common, above most credit card debt annualised. Unpaid property tax is also secured against the house itself, which is what separates it from every other tax — states permit a lien and eventually a tax sale after a statutory redemption period. It is slow and heavily noticed, so it is nearly always avoidable, but it cannot simply be written off.

Renters pay it too, indirectly. Property tax is a cost of holding the building and it is priced into rent like any other, which is why a county's rate shows up in rents as well as in mortgage payments. The difference is visibility: a renter never sees the line, cannot appeal the assessment, and does not benefit when a homestead exemption is claimed.

One timing quirk catches buyers. Many states bill in arrears, so the bill arriving now is for a period you may not have owned the house. Closing statements prorate it, but the first full-year bill after a purchase is the one that surprises people — particularly where the sale itself triggered a reassessment.

What the money funds, and the charges that are not in the rate

Property tax is the main local revenue source in almost every state, and schools are the largest claim on it — commonly half to two-thirds of a bill. The rest funds county government, the municipality, and whichever special districts reach the parcel: fire, library, water, parks, hospital, community college, flood control.

That is why the rate is a sum rather than a number, and why two houses of identical value in the same county can owe different amounts without either being an error. A district boundary running down a street is enough, and boundaries do not follow county or city lines.

Special assessments sit outside the rate entirely. Where a district borrows for a specific project — a sewer extension, road paving, a levee — the cost is levied on the parcels that benefit, for a fixed term, as a separate line. Effective rates computed from tax actually paid include them where they applied; a millage table does not show them at all, and a buyer inheriting a fifteen-year assessment finds out at closing or later.

New construction is the other invisible one. A district's budget divided by its tax base sets the rate, so growth that adds base can hold rates down and growth that adds demand without base pushes them up. It is the reason a fast-growing county can raise rates while a stagnant one does not.

The decade 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 a $400,000 home with assessed value rising 4% a year, ten years costs about $40,201 at the national median rate. At the tenth percentile it is $21,952 and at the ninetieth $75,326 — a spread of $53,374 across the decade on the same house, decided by which county it stands in.

Set that against the mortgage to see the weight of it: the ten-year bill at the median rate is roughly 13% 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 a district can raise without asking you.

Treat the figure as an order of magnitude and not a forecast — it assumes today's effective rate holds, and rates move with budgets and reassessment cycles. What it is reliable for is the comparison, because the gap between two counties is far more durable than either absolute number.

Why property tax and income tax have to be read together

States trade these two against each other, so comparing either one alone reliably produces the wrong answer. Alaska, Florida, Nevada, New Hampshire and 5 others levy no income tax — and several of them sit well above the national median county property rate of 0.84% as a direct consequence. The money is raised either way.

Put it in one arithmetic. A household on $85,000 in a $400,000 house pays up to $6,604 of state income tax in the dearest state and nothing in the nine that levy none. A property rate one point above the median costs $4,000 a year. The two are the same order of magnitude, which is exactly why one without the other decides nothing.

They also fall on different people. Income tax scales with earnings and drops when they do; property tax follows the house and does not care what you earn. That difference is why the swap is close to neutral for a high earner in a modest house and heavily negative for a retiree in an appreciated one — the same state, opposite conclusions.

This site keeps both sides and links them at every level: each county page names its state's income tax treatment, and each state income tax page names the property side. Neither answers the question on its own.

Questions

What is a tax estimator?

In US search it almost always means property tax. County assessors publish "tax estimators" on their own sites, which is why the phrase is so strongly tied to a county name — and why nearly every search for it carries one. Income tax is set by the state and asked about differently, which is why this site keeps the two apart.

Why do I need my county rather than my state?

Because property tax is levied locally and the spread inside a single state is enormous. Across the 3,132 US counties with published data, effective rates run from 0.08% to 3.64% — more than twenty to one on the same house. A state average is close to meaningless; the county figure is the one that applies to you.

Do I need a parcel number?

No, and that is the point. Your 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.

Where do the numbers come from?

Each county's effective rate is its median property tax paid divided by its median home value, both from the US Census Bureau, American Community Survey 5-year 2023. It is a real, federal, citable measure of what owners there actually pay. It is not the millage for your parcel, and we do not claim it is — for that, the county assessor is the authority.

Does the state matter at all for property tax?

Enormously, but through its rules rather than its rate. The homestead exemption, the cap on how fast an assessment can rise and the fraction of value taxed are all set at state level, and they routinely matter more than the rate. Texas exempts $140,000 of value from school tax; South Carolina taxes 4% of a home's value while Texas taxes 100%. We have loaded all 51 of those rulebooks, each read off the state's own publication.