Property tax is calculated by multiplying your home's assessed value by the local tax rate, then dividing by 100

The formula is straightforward: assessed value × tax rate ÷ 100 = annual property tax. If your home is assessed at $300,000 and your local rate is 1.2%, you owe $3,600 per year. The catch is that "assessed value" is not the same as what you paid for the house or what it would sell for today — it is a value set by your county or township assessor, and it often lags behind market prices.

Property tax rates vary dramatically by location. Some counties charge less than 0.5% of assessed value annually; others charge over 2%. The rate depends on what your local government needs to fund: schools, roads, fire departments, libraries, and county services all draw from the same property tax pool. A rate change in your district does not mean your taxes went up — it means the total revenue needed divided by all properties in the area produced a higher or lower percentage.

Most homeowners do not write a check directly to the assessor. If you have a mortgage, your lender requires you to pay property tax through escrow — a monthly amount added to your mortgage payment that the lender holds and pays to the county on your behalf when the bill comes due. If you own your home outright, you receive a bill directly from your county treasurer or tax collector, usually once or twice per year depending on your state.

Key Takeaways

  • Your assessed value is set by a county assessor and is often lower than your home's market value or purchase price.
  • The tax rate is set by your local government and varies by county, township, and school district — it is not a percentage you can negotiate.
  • If you have a mortgage, property tax is collected through escrow and paid by your lender; if you own outright, you pay the county directly.
  • You can challenge your assessed value through a formal appeal process, usually held once per year in your county.
  • Property tax bills are public record and can be looked up by address on your county assessor's website.

How assessors determine your home's value

Assessors do not appraise every home every year the way a bank does before a mortgage. Instead, they use a combination of recent sales data, property characteristics, and formulas to estimate value. They look at comparable homes that sold recently in your area, adjust for differences in size, condition, lot size, and age, and arrive at an assessed value. Some counties use computer-assisted mass appraisal (CAMA) systems that run these calculations automatically across thousands of properties.

The assessed value is typically lower than the actual market value — often 50% to 80% of what the home would sell for. This is intentional: most states cap the percentage of market value that can be taxed. A home worth $400,000 might be assessed at $250,000, meaning you pay tax on $250,000, not $400,000. The exact cap varies by state and sometimes by county within a state.

Assessments happen on a cycle. Some counties reassess every year; others every three to five years. If you have not seen an assessment notice in a while, your county may be in a multi-year cycle and yours is straightforward not due yet. You can find your county assessor's office online and look up your property by address to see when your last assessment was and what value they assigned.

When and how to challenge your assessed value

If you believe your assessed value is too high, you can file a formal objection called an assessment appeal or tax assessment challenge. The process and important date vary by state and county — some allow appeals year-round, others have a narrow window (often 30 to 60 days after you receive your assessment notice). Missing the important date usually means you cannot appeal until the next assessment cycle.

To build your case, gather evidence that your home is worth less than the assessed value. This might include a recent appraisal from a bank or appraiser, a comparative market analysis from a real estate agent, photos of damage or needed repairs, or sales prices of similar homes in your area that sold for less. You do not need a professional appraisal — documentation of comparable sales is often enough.

The appeal process typically involves submitting a written request to your county assessor's office, sometimes followed by a hearing before a board of review or assessment appeals board. Some counties allow you to present your case in writing only; others require you to appear in person or by video. Contact your county assessor's office to learn the specific steps and important date for your location. If you disagree with the board's decision, you may have the right to appeal to a state tax court, though this is rare and usually only worth pursuing if the assessed value is very high.

How property tax affects your monthly mortgage payment

When you have a mortgage, your lender calculates an escrow amount based on your estimated annual property tax, homeowners insurance, and sometimes mortgage insurance. This amount is divided by 12 and added to your monthly payment. If your property tax is $3,600 per year, roughly $300 goes into escrow each month (plus insurance and any other escrowed items).

The lender does not always get the escrow amount right on the first try. If property taxes rise or your home is reassessed higher, your escrow payment may increase at your loan's anniversary date. Conversely, if taxes fall or you paid off mortgage insurance, your payment may decrease. Lenders are required to conduct an annual escrow analysis and notify you of any change at least 10 days before it takes effect.

If your escrow account runs short — meaning the lender did not collect enough to cover the actual tax bill — you may owe a lump sum. If it runs over, you may receive a refund or a credit toward future payments. You can request an escrow analysis at any time if you believe the amount is wrong, and some lenders allow you to make a one-time adjustment without waiting for the annual review.

Tax exemptions and homestead deductions

Many states and counties offer homestead exemptions or homestead deductions that reduce your assessed value or tax bill if you live in the home as your primary residence. These are not the same as federal tax deductions — they are local property tax breaks. A homestead exemption might reduce your assessed value by a fixed dollar amount (say, $50,000) or by a percentage, which directly lowers your property tax bill.

may be able to access and the amount of the break vary widely. Some states offer exemptions only to seniors or disabled homeowners; others offer them to all owner-occupants. You typically must file a form with your county assessor to claim the exemption, and you must recertify every few years to prove you still live there. If you move or rent out the home, you lose the exemption and your taxes go up.

Other exemptions exist for agricultural land, historic properties, and nonprofits. If your property might may have access to for any exemption beyond the standard homestead break, ask your county assessor what forms are available and what the important date is to file.

What happens if you do not pay property tax

If you own your home outright and do not pay property tax, the county will eventually place a tax lien on your property. This means the county has a legal claim against your home for the unpaid amount. You cannot sell or refinance without satisfying the lien. If the debt remains unpaid long enough (usually two to five years, depending on state law), the county may foreclose and sell your home at a tax sale to recover the money owed.

If you have a mortgage, your lender will not let this happen. Your lender pays the property tax from your escrow account and then bills you for the shortfall. If you do not reimburse the escrow account, the lender may declare you in default of your mortgage, which can lead to foreclosure. This is one reason lenders require escrow — they protect their investment by ensuring taxes are paid.

If you are struggling to pay property tax, contact your county treasurer or tax collector to ask about payment plans, deferral programs, or hardship exemptions. Some counties allow you to spread payments over several months or defer taxes if you meet income or age requirements. Acting early is far better than waiting for a lien to be filed.

How property tax differs from income tax and sales tax

Property tax is a wealth tax — you pay it based on what you own, not on what you earn or spend. Income tax is based on your salary or business income; sales tax is based on purchases. Property tax is recurring and local, meaning it is set by your county or township, not by the federal government or your state (though states set the rules for how property tax works).

Property tax is also deductible on your federal income tax return, but only if you itemize deductions and only up to $10,000 per year (as of 2024, under current federal law). This deduction is called the SALT deduction (state and local taxes). If your property tax plus state income tax and sales tax exceed $10,000, you can only deduct $10,000 total. Most homeowners with moderate property taxes will not hit this cap, so the deduction does not help them.

Frequently Asked Questions

Can my property tax go down if my home loses value?

Yes, but only if your county reassesses and finds the lower value. If your home was assessed at $300,000 and the market drops, the next assessment cycle may lower it. You can also file an appeal if you believe the current assessed value is too high. However, if your county is not in a reassessment year, you may have to wait until the next cycle or file an appeal during the allowed window.

What is the difference between assessed value and market value?

Market value is what your home would sell for today. Assessed value is what the county says it is worth for tax purposes, and it is usually lower — often 50% to 80% of market value. The assessed value is used to calculate your property tax bill. You can look up both on your county assessor's website.

Do I have to pay property tax if I own my home outright?

Yes. Property tax is owed by anyone who owns real estate, whether the home is paid off or financed. If you have a mortgage, the lender collects it through escrow. If you own outright, you receive a bill from your county and must pay it directly or face a tax lien and possible foreclosure.

How often does my assessed value change?

It depends on your county's reassessment cycle. Some counties reassess every year; others every three to five years. You can contact your county assessor to find out when your property was last assessed and when the next assessment is scheduled. You can also file an appeal during the allowed window if you believe the current value is wrong.

Can I deduct property tax on my federal income tax return?

You can deduct property tax if you itemize deductions on your federal return, but the total deduction for state and local taxes (property tax, income tax, and sales tax combined) is capped at $10,000 per year. Most homeowners with moderate property taxes do not reach this cap, so the deduction does not reduce their federal tax bill.