An assessor's parcel number, or APN, is a number assigned to parcels of

real property In English common law, real property, real estate, immovable property or, solely in the US and Canada, realty, is land which is the property of some person and all structures (also called improvements or fixtures) integrated with or affixe ...

by the

tax assessor Tax assessment, or assessment, is the job of determining the value, and sometimes determining the use, of property, usually to calculate a property tax. This is usually done by an office called the assessor or tax assessor. Governments need to ...

of a particular

jurisdiction Jurisdiction (from Latin 'law' + 'declaration') is the legal term for the legal authority granted to a legal entity to enact justice. In federations like the United States, areas of jurisdiction apply to local, state, and federal levels. Ju ...

for purposes of identification and record-keeping. The assigned number is unique within the particular jurisdiction, and may conform to certain formatting standards that convey basic identifying information such as the property type or location within the plot map. In the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

, APNs are typically assigned by the local taxing authority, such as the city or county within which the property is located. Many taxing authorities will provide

property tax A property tax or millage rate is an ad valorem tax on the value of a property.In the OECD classification scheme, tax on property includes "taxes on immovable property or net wealth, taxes on the change of ownership of property through inher ...

information to the public, indexed by APN. Alternative terms with the same meaning include: *Assessor's identification number (AIN) *Property identification number (PIN) *Property identification (PID) *Property account number *Tax account number *Sidwell number The term or terms used in any particular jurisdiction are as determined by the authority assigning the numbers. The terms lot and parcel are often used interchangeably, but they have different meanings. A parcel is an identification for taxation purposes, while a lot is a recognized subdivision of property with a written legal description that addresses permissions or constraints upon its development. It is possible for a parcel to have more than one lot. APN numbers and the property boundaries that they describe have become particularly important for the oil and gas industry with recent discoveries of recoverable hydrocarbons in the

Marcellus Shale Marcellus may refer to: * Marcellus (name) * Marcus Claudius Marcellus, Roman commander Places * Marcellus, Lot-et-Garonne, France * Marcellus Township, Michigan ** Marcellus, Michigan, a village in Marcellus Township ** Marcellus Community Sc ...

and related geological formations. Because the geographic regions have no other land survey system (such as the US

Public Land Survey System The Public Land Survey System (PLSS) is the surveying method developed and used in the United States to plat, or divide, real property for sale and settling. Also known as the Rectangular Survey System, it was created by the Land Ordinance of 178 ...

), parcels are the most reliable way to describe a particular area of land. This is especially important for the purpose of legally describing the area covered by an oil and gas lease. The format of APN strings can vary, it is typically a concatenation of the book, page, parcel number. In New York State, they are called "SBL numbers" because they are a concatenation of the section, block, and lot numbers. https://www.tax.ny.gov/pit/property/star/sample-tax-bills.htm

References

{{Reflist Real estate in the United States Identifiers Real estate terminology