Property taxes and use taxes are often imposed in terms of mills, which are units per thousand. For example, a tax rate of 23 dollars of tax per 1000 dollars of value can also be called a tax rate of 23 mills. These taxes are assumed to be annual (or “per annum” or “yearly” or “per year”). Taxes imposed on the basis of assessed or actual value are called ad valorem taxes. The following terms are all synonymous:
Ad valorem rate
Tax rate
Mill rate
Millage rate
Tax levy