The Fairfax County Master Address Repository (MAR) is the authoritative source for site addresses in the county. The MAR application is a user-friendly interface to access official addresses, parcel numbers, and street names. Three search pages—Address, Parcel, and Street—are available. Address and parcel filters provide focused searching and filtered or selected results may be downloaded. MAR data is maintained by the Department of Information Technology’s Geographic Information Systems program (DIT-GIS) and does not include Department of Tax Administration (DTA) data. DTA information may be found on the Fairfax County Real Estate Assessment Site.

The MAR application has three pages with different search and filter functionality, the Address Search, Parcel Search, and Street Search. These can be toggled between by selecting the button on the top right corner of the application. 

The Address Search page offers tools that make it easier to locate valid addresses in Fairfax County. As criteria are applied to the different filters, the table and map filter automatically. Available filters include address number, street name and type, city, ZIP code, parcel ID number, subdivision, and created and expired date ranges. Current addresses are displayed by default, but the "status" filter can show historical or all addresses. Filtered or complete address results can be exported to CSV through the table’s action menu.

The Parcel Search page supports validation of parcel identification numbers (PINs) within Fairfax County, including parcels with or without associated addresses. The PIN search filters to the parcels that match the criteria and zooms to their location on the map. The toggle options below the PIN search filter to only those parcels that do or do not have associated addresses. 

The Street Search page provides the ability to search for street names, both with addresses and without. This page allows searching by street name, street type, and status, as well as ranges for created date. The status can be used to determine if a street name is already in use or has been reserved in Fairfax County.

The address and parcel data may be downloaded from the Geospatial Open Data Portal.

Disclaimer

In no event shall Fairfax County be liable for any damages, including but not limited to loss of data, lost profits, business interruption, loss of business information, or any other pecuniary loss that might arise from the use of this information. Read the full Fairfax County GIS Disclaimer.

MAR does not include addresses in the City of Fairfax, the City of Falls Church, Arlington County, or the City of Alexandria. MAR also does not include unit numbers for apartment addresses.