GIS & Mapping

Snohomish County has GIS / Mapping divisions located in the offices of the Assessor, Auditor, Information Services, Planning and Development Services, and Public Works.
Assessor Responsibilities
The assessor is responsible for maintaining most of Snohomish County's cadastral (land ownership) data, administrative taxing district boundaries and Public Land Survey data in GIS compatible formats to support the county's hard copy and digital mapping needs.

The majority of GIS data maintained by the Assessor's Office is available for download from our FTP site. A complete listing of data available for download can be viewed on our assessor data page.

Available Maps
  • Snohomish County Online Property Information (SCOPI) - An interactive map tool you can use to search for assessment information using either your parcel number or street address.
  • TRSQ Maps (also called Assessor maps or parcel maps) - Look up an online map containing your property using Township, Range, Section, and Quarter.
  • Flood Plain Maps - Part of the planning and development of flood hazard management plans for the main rivers; which includes technical assistance and emergency response to citizens, businesses, and agencies to prevent flooding and respond to flood emergencies. (Maintained by Public Works Surface Water Division) 
All maps, data, and information set forth herein (''data''), are for illustrative purposes only and are not to be considered an official citation to, or representation of, the Snohomish County Code. Amendments and updates to the data, together with other applicable County Code provisions, may apply which are not depicted herein. Snohomish County makes no representation or warranty concerning the content, accuracy, currency, completeness, or quality of the data contained herein and expressly disclaims any warranty of merchantability or fitness for any particular purpose. 

All persons accessing or otherwise using this data assume all responsibility for use thereof and agree to hold Snohomish County harmless from and against any damages, loss, claim, or liability arising out of any error, defect, or omission contained within said data. Washington State Law, Chapter 42.56 Revised Code of Washington (RCW), prohibits state and local agencies from providing access to lists of individuals intended for use for commercial purposes and, thus, no commercial use may be made of any data comprising lists of individuals contained herein.

Special Notes
Snohomish County does not provide sanitary sewer service or water service and does not provide mapping data for these services. Zoning within the boundary of incorporated cities is the responsibility of each city individually. If you are seeking this type of data, please contact cities and sewer or water districts providing those services in your area of interest. 

Some data used by the county is proprietary in nature and may not be distributed by the county. Examples of this type of data are street centerlines and some aerial imagery.