Property Tax Calculator
Value & rate
Your result will appear here
Fill in the fields and this updates as you type.
Know what this estimate is based on
- Jurisdiction
- United States — property tax is levied by counties, municipalities and school districts, each with its own rate, assessment ratio and exemptions
- Rules and time period
- The assessed value, rate and exemptions are the ones you enter. Reassessment cycles and levy rates are set locally and change year to year.
- Scope and limitations
- Arithmetic on the figures you supply. It does not apply your jurisdiction's assessment ratio, caps on annual increases, homestead or senior exemptions, or special district levies. Your assessor's notice is the document that binds.
- Source links checked
- Sep 19, 2026
Built and regression-tested by Smart Tools Lab. It has not been individually reviewed by a licensed financial, tax, or legal professional.
How to use
- 01
Enter the assessed value of the property. On your assessment notice this may be the full market value or a fraction of it — the two are different numbers and using the wrong one is the most common source of a wildly wrong estimate.
- 02
Enter your property tax rate. If your jurisdiction quotes a millage rate instead, divide by ten to get a percentage: 20 mills is 2%.
- 03
Open Advanced and set the assessment ratio if your area assesses at a fraction of market value. Enter market value above and the ratio here, and the calculator works out the assessed figure for you.
- 04
Still in Advanced, enter any homestead or other exemption. It comes off the assessed value before the rate applies, so its effect is the exemption multiplied by your rate — not the exemption itself.
- 05
Read the annual tax, the monthly figure and your effective rate against market value. The effective rate is the one to compare between neighborhoods, because it is unaffected by local assessment conventions.
- 06
Use the monthly figure in your housing budget. Property tax is usually collected through mortgage escrow, so it is part of the payment whether or not you thought about it.
Formula
Property tax is a rate applied to a value that has usually already been adjusted twice: Assessed value = market value × assessment ratio Taxable value = max(0, assessed value − exemptions) Annual tax = taxable value × tax rate Monthly = annual ÷ 12 Effective rate = annual tax ÷ market value Many jurisdictions quote the rate in mills rather than percent. One mill is one dollar per thousand of taxable value, so 20 mills is 2% — and a rate that looks alarming in mills is often ordinary once converted. The effective rate is the figure worth comparing. A county assessing at 40% of market value with a 4% rate and one assessing at 100% with a 1.6% rate produce exactly the same bill, and only the effective rate makes that visible.
Example
A home with a market value of $400,000 in a county that assesses at 100%, with a 1.2% rate and a $25,000 homestead exemption. The assessed value is $400,000, the taxable value is $375,000, and the annual tax is $4,500 — $375 a month. The effective rate against market value is 1.125%, and the exemption is saving $300 a year, not $25,000. The same home in a county that assesses at 40% of market value with a 3% rate. The assessed value is $160,000, and without an exemption the annual tax is $4,800. The rate looks two and a half times higher and the bill is within a few hundred dollars — which is exactly why the headline rate tells you almost nothing on its own. Over ten years at today's bill that first home costs $45,000 in property tax, before any reassessment.
Definitions
- Market value
- What the property would sell for in an ordinary transaction. The starting point, though not always the figure the tax is applied to.
- Assessed value
- The value the taxing authority actually uses. It equals market value multiplied by the assessment ratio, and in many places is deliberately well below what the home would sell for.
- Assessment ratio
- The fraction of market value that is assessed — 100% in some states, 40% or less in others. It is why headline tax rates are not comparable across jurisdictions.
- Millage rate
- A rate quoted in dollars per thousand of taxable value. One mill is 0.1%, so 20 mills is 2%.
- Taxable value
- Assessed value after exemptions. This is the figure the rate is finally applied to.
- Homestead exemption
- A reduction in taxable value for an owner-occupied primary residence. Its value to you is the exemption multiplied by your tax rate, not the exemption amount.
- Effective tax rate
- Annual tax divided by market value — the only figure that compares fairly across places with different assessment conventions.
- Reassessment
- The periodic revaluation of property. Depending on the state it may happen annually, on a cycle, or only when the property changes hands.
- Assessment cap
- A limit on how fast assessed value may rise year to year, common in states that protect long-term owners from rapid market appreciation.
- Escrow
- The account your lender uses to collect property tax monthly with your mortgage payment and pay the bill when it falls due. It is why a tax increase shows up as a mortgage payment increase.
- SALT deduction
- The federal itemized deduction for state and local taxes, including property tax. It has been subject to a statutory cap — check the current year's limit, as it has changed.
- Special assessment
- A separate charge for a specific local improvement such as a road or sewer, levied on the properties that benefit. It is not part of the general rate.
- Appeal
- The process for challenging an assessment you believe is too high, usually within a short window after the notice and usually requiring comparable sales as evidence.
- PITI
- Principal, interest, taxes and insurance — the four components of a typical mortgage payment. Property tax is the T, and it is the component that keeps rising after the loan is fixed.
Good to know
Three numbers, and why the rate alone tells you nothing
A property tax bill is the product of three things: the value the authority assigns, the exemptions you qualify for, and the rate. People compare the third and ignore the first two, which is why headline rates across jurisdictions are close to meaningless. Market value is what the property would sell for. Assessed value is what the taxing authority actually applies the rate to, and in many places it is deliberately a fraction of market value — the assessment ratio. Some states assess at 100%; others at 40%, 25% or less, with the rate set correspondingly higher to raise the same revenue. A county assessing at 40% with a 3% rate and one assessing at 100% with a 1.2% rate produce the same bill on the same house. The first looks two and a half times more expensive and is not. This is why the effective rate — annual tax divided by market value — is the only figure worth comparing between places. It strips out the local convention and leaves the number you actually care about: what fraction of your home's worth leaves your account every year. Many jurisdictions add a further layer by quoting the rate in mills. One mill is one dollar per thousand of taxable value, or 0.1%. A rate of 24 mills is 2.4%. And the figure on your bill is frequently the sum of several separate millages — county, municipality, school district, sometimes a library, fire or water district — each set by a different body with its own budget. When you enter a rate into this calculator, make sure it is the combined rate applied to your property, not one component of it. It is also worth knowing that the rate is not really one decision. Each taxing body sets its own levy against the total assessed value in its district, so your rate moves when a school district passes a bond, when the county budget grows, or — less intuitively — when total assessed values in the district fall and the rate rises to raise the same revenue. That last mechanism catches people out badly: in a falling market, assessments can drop while bills stay flat or rise, because the rate adjusted to compensate. The bill follows the budget more closely than it follows the market.
How your assessment is set, and how often it moves
Assessments are produced by mass appraisal, not individual valuation. The assessor's office models values across thousands of properties using sales data, characteristics, and location, then applies the model. Nobody visits most homes, and the result is an estimate that is usually reasonable in aggregate and sometimes wrong in individual cases. How often it updates varies enormously. Some states reassess annually. Others run multi-year cycles, so your value may be based on a market that no longer exists. And some reassess primarily on transfer — meaning the value resets when the property is sold, and a new owner can face a dramatically higher bill than the person who sold to them, for the identical house. Several states cap how fast assessed value may rise for a continuing owner, regardless of what the market does. These caps protect long-term owners from being taxed out of appreciating neighborhoods, and they create the striking situation where two identical adjacent houses carry very different bills — one owned for thirty years, one bought last spring. That is the system working as designed, not an error, and it makes a neighbour's tax bill a poor guide to your own. Understanding which regime applies where you live tells you what to expect. In an annual-reassessment state, rising prices mean rising taxes every year. In a transfer-triggered state, your bill is stable until you move — and then it resets to today's value, which is a cost of moving that rarely appears in the arithmetic people do when deciding whether to. This variation is also why national comparisons of property tax are close to meaningless at the individual level. A state's average effective rate is an average across enormously different counties, and within a county across districts with different school funding. Two homes of identical value a few miles apart, in different school districts, can carry bills differing by thousands. When assessing where to buy, the figure worth obtaining is the actual current bill for the specific property, which is almost always public record and takes minutes to look up.
Exemptions: worth claiming, routinely overestimated
A homestead exemption reduces the taxable value of an owner-occupied primary residence. Its value to you is the exemption multiplied by your tax rate — not the exemption amount. A $50,000 homestead exemption at a 1.2% rate saves $600 a year. That is real money and worth claiming, but people frequently hear "$50,000 exemption" and expect an effect eighty times larger than the one they get. The exemption comes off the value, not off the bill. Beyond the homestead exemption, most jurisdictions offer several others that are rarely applied automatically. Senior exemptions or assessment freezes for owners above a certain age. Exemptions for veterans, often larger for service-connected disabilities. Exemptions for people with disabilities. Agricultural or conservation use valuations that assess land on its current use rather than its development potential. Relief programs for low-income owners. Almost all of these require an application, sometimes once and sometimes annually, and they are among the most consistently unclaimed reliefs in local taxation. An eligible owner who never applied simply pays more, indefinitely, with no notification that they qualified. The practical step is to read your assessment notice — which lists the exemptions currently applied — and check your county assessor's published list against your circumstances. It takes an hour and it is the highest hourly rate most homeowners will ever earn. One warning: exemptions tied to occupancy usually end when the property stops being your primary residence. Converting a home to a rental without notifying the assessor can produce back taxes and penalties later. Exemptions also interact with each other in ways worth checking. Some are subtracted from assessed value, some apply only to particular components of the combined rate — a school levy but not a county one — and some cap growth rather than reducing value. Two exemptions that each look worth several hundred dollars may not simply add together. The assessor's office can say what a specific combination produces on a specific property, and asking is more reliable than assuming, particularly where a senior or disability exemption is being layered on top of a homestead one.
Appealing an assessment
Assessments can be challenged, and appeals succeed more often than most owners expect — because mass appraisal produces individual errors and the assessor has no way to find them without being told. What you are challenging is the *valuation*, not the rate. The rate is set through budget decisions by elected bodies and is not appealable. The argument that your taxes are too high is not an argument the appeals board can act on. The argument that your assessed value exceeds what your property would sell for, or exceeds what comparable properties are assessed at, is. The window is short. It typically opens when assessment notices are mailed and closes within a few weeks. Miss it and you generally wait a full year, paying the disputed amount in the meantime. Evidence is what decides it. Recent sales of genuinely comparable properties — similar size, age, condition, location — carry the most weight. So do documented defects the model could not see: a failing roof, foundation problems, a location issue that depresses value. A recent arm's-length purchase price below the assessment is strong evidence. An independent appraisal is stronger still and costs several hundred dollars, which is worth it when the disputed amount is large. What does not work: comparing your bill to a neighbour's without accounting for their exemptions or when their property was last reassessed, arguing that you cannot afford the increase, or objecting to how the money is spent. Most jurisdictions run an informal review first, which resolves many cases without a hearing. That is usually the sensible place to start, and a successful appeal often benefits you for several years rather than one. It also helps to know what the assessor already believes about your property, because the record often contains errors that nobody has ever checked. Square footage, number of bathrooms, lot size, the presence of a basement or garage, even whether a demolished structure is still listed — all of it feeds the model. Property record cards are generally public, and finding that your home is recorded with an extra 400 square feet is both the easiest correction to make and one that can reduce the assessment for every year afterwards, not just the one you appealed.
Escrow: why a tax change arrives as a mortgage change
Most homeowners with a mortgage never pay a property tax bill directly. The lender collects roughly one-twelfth of the annual amount with each monthly payment, holds it in an escrow account, and pays the county when the bill falls due. This is convenient and it obscures what is happening. Your property tax becomes a component of a single monthly figure — the T in PITI, alongside principal, interest and insurance — and rises without any separate notice arriving. When taxes increase, the lender performs an escrow analysis, usually annually. Two things then happen at once. The monthly collection rises to cover the new annual amount, and a shortfall for the months already underpaid is spread over the coming year. That is why a modest tax increase can produce a disproportionate jump in the mortgage payment: you are paying the higher rate *and* catching up on the gap. The reverse occurs after a successful appeal or a new exemption, though refunds of escrow surpluses can take a cycle to appear. Two practical consequences follow. First, a fixed-rate mortgage does not mean a fixed housing payment — the interest is fixed and the taxes are not, which is worth remembering when assessing affordability over a long horizon. Second, the payment continues after the loan is repaid. A paid-off house still owes property tax every year for as long as you own it, and retirement plans that assume housing becomes free at payoff can understate ongoing costs by several hundred dollars a month. There is a related trap when a mortgage is refinanced or sold to another servicer. Escrow accounts do not always transfer cleanly, exemptions occasionally fail to carry across, and a new servicer estimating the tax rather than using the actual bill can set the monthly collection materially wrong in either direction. The first escrow statement after a servicing change is worth reading properly rather than filing, because an error caught in month one is a phone call and an error caught in month eleven is a large catch-up payment.
Property tax when buying, selling and deducting
At closing, property taxes are prorated between buyer and seller so each pays for the portion of the year they owned the property. The mechanics depend on whether your jurisdiction bills in arrears or in advance, and the settlement statement shows the adjustment as a credit or a charge. It is handled by the closing agent rather than by you, but it is worth checking, because errors in proration are not rare and are easier to fix before closing than after. Buyers should look past the seller's current bill. In a transfer-triggered reassessment state, the tax will reset to reflect your purchase price, and the previous owner's figure may bear no relation to what you will pay. Their exemptions do not transfer either — a senior or veteran exemption reducing their bill disappears when you take title. Estimating your future payment from the current bill is one of the more expensive mistakes in home buying, and it is entirely avoidable by asking the assessor what the property would be assessed at post-sale. On the federal return, property tax is an itemized deduction as part of state and local taxes, and that combined deduction has been subject to a statutory cap in recent years. The cap has changed, so confirm the figure for the year you are filing. The deduction only helps if you itemize at all, and the size of the standard deduction means many homeowners no longer do — which means for a large share of owners, property tax is simply a cost with no federal offset. Rental and business property is different: property tax there is an ordinary operating expense, deductible in full against rental income without reference to the itemized cap. Buyers should also be aware that new construction and recent improvements are assessed separately and often later. A home bought before a renovation was added to the roll can carry a bill that jumps sharply once the assessor catches up, sometimes a year or more after closing. Where a property has been recently extended or rebuilt, asking whether the improvement is reflected in the current assessment prevents an unpleasant surprise that arrives after you have already set your budget around the old figure.
Budgeting for a cost that never stops rising
Property tax behaves unlike the rest of a housing budget. The mortgage payment is fixed for thirty years and then ends. Insurance drifts. Property tax rises with both the value of the property and the funding needs of local government, and it never ends at all. Over a long horizon this compounds into a substantial figure. A $4,500 annual bill growing at 3% a year totals around $52,000 over ten years and roughly $164,000 over twenty-five. That is a real cost of ownership, and it is invisible in the calculation most buyers do, which weighs a monthly mortgage payment against a monthly rent. Two practical implications follow. For buyers, affordability should be assessed on the full payment including taxes and insurance, with an allowance for growth — not on principal and interest. A house that is comfortable at today's tax bill can be uncomfortable at the bill eight years from now, particularly in a jurisdiction that reassesses annually in an appreciating market. For retirees, property tax is often the largest remaining housing cost once the mortgage is gone, and it is the one that keeps rising against a fixed income. This is where senior exemptions and assessment freezes matter most, and where they are most often unclaimed. It is also a genuine reason people relocate later in life — not because the house became unsuitable, but because the tax on it outgrew the income supporting it. The monthly figure this calculator produces is the one to carry into a budget. Annual bills are easy to underestimate precisely because they arrive once or twice a year rather than every month. For owners already in place, the single most useful habit is reading the annual assessment notice rather than discarding it. It states the value being used, the exemptions applied, and the deadline to challenge — all three of which are the only levers you have, and all three of which expire quietly if ignored. Most people never open it, which is why assessments that are simply wrong persist for years and why exemptions that were never claimed stay unclaimed. Fifteen minutes a year is the entire commitment.
What this calculator does not model
This tool applies one rate to one value, after an assessment ratio and an exemption. That is the structure of a property tax bill everywhere, and with your actual assessment notice in front of you it produces a close estimate. What it does not do is reproduce the detail of any particular jurisdiction. It uses a single combined rate, where a real bill is usually the sum of several separate millages set by different authorities — county, city, school district and any special districts — each of which can change independently. It does not model special assessments: separate charges for a specific local improvement such as a road, sewer or streetlight scheme, levied on the properties that benefit and appearing on the same bill. It does not apply assessment caps that limit how fast a continuing owner's taxable value may rise, nor the reassessment that follows a sale in states that trigger on transfer. It applies one exemption amount, where a real bill may combine several with different eligibility rules, and where some exemptions reduce value while others apply to specific components of the rate. And it does not know your state's rules on any of this, because they differ profoundly — property tax is the most locally variable major tax in the United States. The way to use it well is to take the assessed value and combined rate directly from your assessment notice or the assessor's website, rather than estimating them. With those two figures the result should be close to your actual bill. Use it to test scenarios — what a successful appeal is worth, what an exemption you have not claimed would save, what a purchase at a different price would cost annually — and treat the county's own figure as authoritative. The wider point is that property tax is unusually within your influence compared with other taxes. You cannot appeal your income tax bracket, but you can appeal a valuation, claim an exemption, correct a record error and choose a district before buying. The tax is also unusually persistent — it outlives the mortgage and rises with time. That combination of controllable and permanent makes it worth more attention than most homeowners give it, and this calculator is most useful when the numbers going into it come from your actual notice rather than an estimate.
Frequently asked questions
Is my assessed value the same as what my house is worth?
Often not. Many jurisdictions assess at a fraction of market value — 40%, 50%, 70% — and the rate is set to suit. Your assessment notice will say which convention applies. Entering market value where the tax is applied to a fraction of it overstates your bill by the inverse of that fraction — at a 40% assessment ratio, two and a half times the real amount. It is the mistake worth checking for first.
What is a mill and how do I convert it?
A mill is one dollar of tax per thousand dollars of taxable value, which is 0.1%. Divide the millage rate by ten to get a percentage: 15 mills is 1.5%, 32 mills is 3.2%. Jurisdictions that quote mills often add several separate millages together — county, city, school district — so check whether the figure you have is the combined rate.
How much is a homestead exemption actually worth?
The exemption multiplied by your tax rate, not the exemption itself. A $50,000 exemption at a 1.2% rate saves $600 a year. That is a real saving worth claiming, but it is not the headline number, and people frequently overestimate it by a factor of eighty.
Why did my property tax go up when I did nothing to the house?
Two things move it independently: the assessed value and the rate. A reassessment can raise your value because the market moved, and taxing bodies can raise the rate to fund budgets. Either alone raises your bill, and both often move in the same year. In some states a sale triggers a reassessment, which is why a new owner's bill can jump sharply above the previous owner's.
Can I challenge my assessment?
Yes, and it succeeds more often than people expect. The window is usually short — measured in weeks after the notice — and the case is made with comparable sales showing your assessment is out of line with similar properties. You are challenging the valuation, not the rate; the rate is set by budget decisions and is not appealable.
Is property tax deductible on my federal return?
It is an itemized deduction for state and local taxes, subject to a statutory cap that has changed over recent years and is worth confirming for the year you are filing. It only helps if you itemize at all, which the large standard deduction means many homeowners no longer do.