GIS Open Data
A variety of Assessor's Office data is available in electronic format for download from the Snohomish County Open Data Portal. Snohomish County has made every effort to make the data freely and readily accessible. Due to the variety of user system configurations and security software, the Assessor's Office is not able to provide technical assistance if you are unable to download the data.
Spatial Data (GIS)
Snohomish County has a distributed GIS environment with GIS work groups located in Public Works, Planning and Development Services, Emergency Management, Information Technology, and the Assessor's Office, among others.
The Assessor is the custodian of a variety of spatial data layers, some of the more popular layers that are available on the open data portal are:
- All Parcels (Past and Present) - Updated three times per week
- Appraisal Neighborhoods - Updated daily
- Cadastral Annotation - Updated three times per week
- City Boundaries - Updated as needed
- Current Parcels - Updated three times per week
- Easements - Updated three times per week
- Municipal Annexation History - Updated as needed
- Parcel Centroids - Updated three times per week
- Public Land Survey Grid – Updated three times per week
- Recent Property Sales – Updated daily
- Right of Way - Updated three times per week
- Subdivision Boundaries - Updated three times per week
- Subdivision Lots - Updated three times per week
- Tax Code Areas - Updated as needed
Tabular Data
Selected extracts from our tabular data systems are available for free download.
- Assessment roll - Microsoft Excel Version - Updated three times per week
- Assessment roll - CSV Version - Updated three times per week
- Parcel Legal Descriptions – Excel Version - Updated three times per week
Unrecorded Plats
A zip file containing a collection of PDF scans of unrecorded plats.
The Assessor's Office will continue to enhance its data offerings in the future.