How Oklahoma property tax is calculated

Every county in the OKC metro uses the same four steps. Only the assessment ratio and the mill levy for your tax district differ.

  1. Taxable market value. The assessor's estimate of fair cash value, limited in most years by the constitutional cap (3% a year for homestead or agricultural property, 5% for other property). The cap does not apply in a year the property sells or is improved (Okla. Const. Art. X §8B).
  2. × Assessment ratio. Oklahoma County 11%, Cleveland County 12%, Canadian County 12%, Logan County 11%, Grady County 11%, McClain County 11%, Lincoln County 11%, Pottawatomie County 12%, Kingfisher County 11% (sources). The result is the gross assessed value.
  3. − Exemptions. Homestead removes $1,000 of assessed value; the additional homestead exemption removes another $1,000 for qualifying low-income households.
  4. × Mill levy ÷ 1,000. One mill is $1 of tax per $1,000 of assessed value. The levy is the sum of county, city, school district and technology center/college levies for your tax district.

Worked example

A home with a $300,000 taxable market value in Edmond (Oklahoma County, Edmond #12 school district, 105.16 mills in 2025):
$300,000 × 11% = $33,000 assessed → − $1,000 homestead = $32,000 → × 105.16 ÷ 1,000 = $3,365 per year.

Levies are certified each fall and bills are mailed in late fall. Rates can change every year as voters approve bonds and as valuations change.

FAQ

What is a mill in Oklahoma property tax?

One mill equals $1 of tax for every $1,000 of assessed value.

Who sets property tax rates in Oklahoma?

Rates come from county, city, school district and technology center levies, many approved by voters, and are certified by the county excise board; the county assessor does not set rates.

Data last verified against official sources: October 16, 2026.