Calculateur de taxe fonciere

Property Tax Calculator

Property taxes are one of the largest ongoing costs of homeownership, often adding $300-$1,000 or more to your monthly housing payment. This calculator estimates your annual and monthly property tax based on your home’s assessed value and local tax rate, helping you budget accurately and avoid surprises when your first tax bill arrives.

How Property Taxes Are Calculated

The core formula is straightforward:

Annual Property Tax = Assessed Value x Effective Tax Rate

However, the inputs are less simple than they appear. Assessed value is not always the same as market value — some states (like California and Massachusetts) assess at 100% of market value, while others (like Louisiana and Colorado) apply an assessment ratio of 10%-20%, then apply a higher mill rate to that lower base. The result is the same tax bill in the end, but the numbers look very different on paper. Mill rate expresses the tax per $1,000 of assessed value: a 12 mill rate equals a 1.2% effective rate.

Worked Examples

Example 1 — Texas suburb, high rate with exemption Home market value: $380,000. Texas assesses at 100%, so assessed value is $380,000. Homestead exemption: $100,000 (for school taxes). Taxable value: $280,000. Effective rate: 2.1%. Annual tax: $5,880. Monthly escrow: $490.

Example 2 — Midwest mid-size city, average rate Home market value: $275,000. Assessed at 100%. No exemptions claimed. Tax rate: 1.4%. Annual tax: $3,850. Monthly escrow: $321. If this homeowner applied for the available homestead exemption of $25,000, taxable value drops to $250,000 and annual tax falls to $3,500 — saving $350/year.

Example 3 — Northeast high-value home, New Jersey Home market value: $650,000. Assessed at 100%. Rate: 2.3%. Annual tax: $14,950. Monthly escrow: $1,246. This significantly exceeds the federal SALT deduction cap of $10,000 per year, so the homeowner only receives partial federal deduction benefit.

Property Tax Reference Table

Divide annual amount by 12 for monthly escrow contribution.

When to Use This Calculator

• Before making an offer on a home, to understand the true monthly cost including property taxes
• When comparing homes in different counties or states where tax rates vary significantly
• To estimate how much to set aside in escrow if your lender does not manage it for you
• When applying for exemptions, to calculate how much each exemption saves annually
• When appealing your assessed value, to model what a lower assessment would mean for your annual bill

Common Mistakes

1. Using the listing agent’s tax figure without verifying — the tax shown in a listing reflects the prior owner’s situation, which may include exemptions you won’t qualify for (like a senior exemption). After purchase, reassessment could raise the bill substantially.
2. Ignoring the difference between assessed value and market value — in states like Mississippi, assessed value is 10% of market value, but mill rates are very high. Plugging in market value directly will produce a wildly incorrect estimate in those states.
3. Forgetting that taxes can change — many states reassess annually or every two years. If you buy after a period of rapid appreciation, your reassessment after purchase could significantly increase the bill.
4. Missing available exemptions — homestead exemptions are not automatic in most states. You must apply, usually within the first year of ownership. In Texas, a $100,000 school homestead exemption saves roughly $2,000/year at a 2% rate; many new owners never file and pay the higher bill for years.

Current Context for 2026

Home values in many markets rose 20%-40% between 2020 and 2024, and reassessments are working their way through county systems. Homeowners in states with annual reassessment — Texas, New Jersey, Illinois — are seeing tax bills reflect those higher values in 2025 and 2026. In California, assessed value is still capped at 2% annual growth under Prop 13 for long-term owners, but new buyers are assessed at full purchase price immediately. The federal SALT deduction cap of $10,000 (in place since 2018) continues to make high-property-tax states more expensive in after-tax terms for many households, particularly those in New Jersey, Connecticut, and Illinois.

Tips

1. Locate your exact assessed value on your county assessor’s website before using any calculator — it may be 20%-30% below current market value depending on your state
2. If your assessed value is higher than what comparable homes sold for in the past 12 months, file a property tax appeal — success rates run 30%-50% and the process is usually free
3. Apply for the homestead exemption immediately after closing — most counties require an application by April 30 of the year following purchase
4. In high-tax states, factor property tax into your affordability calculation before setting a home price target — in parts of New Jersey, a $500,000 home can carry $12,000/year in taxes
5. Ask your mortgage servicer each year to confirm your escrow analysis is accurate — many homeowners are under-escrowed and face a large catch-up payment at year-end
6. Senior homeowners over 65 should check for additional senior freeze programs that cap assessed value increases, available in states including New Jersey, Illinois, and Texas

Related Calculations

• Mortgage Calculator — includes a field for monthly property tax so you see the full PITI payment
• Closing Cost Calculator — prepaid property taxes at closing are typically 2-6 months of the annual bill
• Rent vs Buy Calculator — property tax is one of the key ongoing costs that shifts the rent vs buy break-even point
• Real Estate Affordability Calculator — factors property taxes into the maximum home price calculation