Property Tax Calculator (Annual Bill & Monthly Escrow)
Enter your assessed value and your area's effective tax rate to see the annual bill and the monthly escrow slice it adds to a mortgage payment. An optional growth rate projects the next five years of bills.
Your county assessor's value, which can differ from market value
Annual tax as a share of value; your county sets the real number
How fast assessments drift up; set 0 for a flat projection
Annual property tax
$3,850
1.10% effective rate on $350,000
Monthly (escrow) amount
$321
what rides along with a mortgage payment into escrow
Next 5 years, total
$20,036
with assessments growing 2% per year
Five-year projection
| Year | Assessed value | Annual tax | Per month |
|---|---|---|---|
| 1 | $350,000 | $3,850 | $321 |
| 2 | $357,000 | $3,927 | $327 |
| 3 | $364,140 | $4,006 | $334 |
| 4 | $371,423 | $4,086 | $340 |
| 5 | $378,851 | $4,167 | $347 |
An estimate, not a bill: real taxes depend on your county's assessment schedule, local levies, and any exemptions you qualify for. Your county assessor's site has the actual rate and assessed value.
One multiplication, two slippery inputs
The formula could not be simpler: assessed value times the effective tax rate equals the annual bill, divided by twelve for the monthly escrow amount. The work is in the inputs. Effective rates are set by counties, cities, and school districts together, and they vary enormously: statewide averages run from roughly 0.3% at the low end to about 2.3% at the high end, and individual counties spread wider still. No national calculator knows your number, so treat the slider as a way to explore and your county assessor's website as the source of truth. Your last tax bill divided by your home's value gives you the effective rate you're actually paying.
Assessed value is not the price on the listing
Counties tax the assessed value, which is their administrative estimate, not what your home would sell for. Depending on the state, assessments may lag the market by years, apply a ratio to market value, or be legally capped in how fast they can climb, and exemptions can shave taxable value further. This is why a neighbor's bill can differ from yours on an identical floor plan. When you buy, watch for the reset: many counties reassess at sale price, so the previous owner's bill can understate what yours will be. It's worth pricing that into the affordability math before you fall for a house.
Sizing the bill: a $350,000 example
At a 1.1% effective rate, a $350,000 assessment owes $3,850 a year, about $321 a month riding along inside the mortgage payment. Let assessments drift up 2% a year and the fifth-year bill is roughly $4,167, with about $20,000 paid over the five years. Two planning notes fall out of that. First, property tax never amortizes away: unlike the loan, it rises with the home's value, which matters for long-horizon budgets and retirees. Second, if you own without escrow, the bill lands in one or two lump payments a year, which is exactly the kind of irregular expense a sinking fund exists to smooth. At closing, several months of it get collected upfront, a line the closing cost calculator accounts for.
Frequently asked questions
What is an effective property tax rate?
Your actual annual tax bill divided by your home's value. It bundles every layer of local taxation, county, city, school district, and special levies, into one honest percentage. It's more useful than any single advertised millage rate because it reflects what you really pay.
How do I find my real property tax rate?
Check your county assessor's or treasurer's website, or divide last year's total tax bill by your assessed value. Rates are set locally, so even neighboring counties can differ meaningfully. If you're shopping for a home, listings and county records usually show the current owner's actual bill.
What's the difference between assessed value and market value?
Market value is what a buyer would pay today. Assessed value is what your county uses to calculate tax, and it often lags the market, applies an assessment ratio, or is capped in how fast it can grow. Exemptions, like a homestead exemption, reduce it further, which is why two identical houses can owe different taxes.
Why did my property tax go up when the rate didn't change?
Because the other half of the equation moved: your assessment. Reassessments after rising home prices, the end of a cap or exemption, or new voter-approved levies all raise the bill without the headline rate changing. That's why this calculator lets you project assessment growth.
Is property tax included in my mortgage payment?
Usually, through escrow. The servicer collects one-twelfth of the estimated annual tax with each payment and pays the county when the bill comes due. When taxes rise, the servicer recalculates and your monthly payment rises too, even though the loan itself never changed.
Does this calculator save my numbers?
No. Everything runs in your browser and nothing you type is stored or sent anywhere.
Want this to update itself?
Stoia connects your real accounts and keeps the full picture current: net worth, budgets, and goals. Launching in 2026.