A mill rate, often referred to as a millage rate, is used to calculate property taxes by multiplying it by the value of a property. A mill is one one-thousandth of a dollar, and in property taxes, 1 mill equals $1 per each $1,000, and 1 mill also equals 0.1%. All states and Washington, DC impose property taxes but not always at the state level. Many do so at the municipal or county level.