A property tax (or millage tax) is an ad valorem levy on the value of property that the owner is required to pay. The tax is levied by the governing authority of the jurisdiction in which the property is located; it may be paid to a national government, a federated state or a municipality. Multiple jurisdictions may tax the same property.

There are three species or types of property: land, improvements to land (immovable man-made objects, such as buildings), and personal property (movable man-made objects). Real property (also called real estate or realty) means the combination of land and improvements. Under a property tax system, the state requires and/or performs an appraisal of the monetary value of each property, and tax is assessed in proportion to that value. Forms of property tax used vary between countries and jurisdictions.

A special assessment tax is sometimes confused with property tax. These are two distinct forms of taxation: one (ad valorem tax) relies upon the fair market value of the property being taxed for justification, and the other (special assessment) relies upon a special enhancement called a "benefit" for its justification.

The property tax rate is often given as a percentage. It may also be expressed as a permille (amount of tax per thousand currency units of property value), which is also known as a millage rate or mill levy. (A mill is also one-thousandth of a currency unit.) To calculate the property tax, the authority will multiply the assessed value of the property by the mill rate and then divide by 1,000. For example, a property with an assessed value of US $50,000 located in a municipality with a mill rate of 20 mills would have a property tax bill of US $1,000 per year.[1] In more fam