Thurston GeoData CenterThurston County, WA, US Post Office assigned zip code areas. The purpose of this data is as a general reference only and actual mailing zip codes should be obtained from the US Postal Service . This layer was originally created using USPS TIGER Zip File 2007 tied to 2000 Census Data. It was updated in 2016 using a zip code layer created by TCOMM 911 based off of addressing points. Generally the boundaries between zip code areas have been moved to be coincidental with Thurston County Assessor's Parcel boundaries. As parcels shift, due to correction, or are changed by subdivision, merge, BLA, etc. the boundaries may become disconnected. Periodically adjustments may be made to realign these boundaries with parcels however there is no regular maintenance plan in place. This layer should be used in conjunction with the Zip Code Points layer which is used to show zip codes associated with US Post Office Box Locations. For example in smaller jurisdictions, like Bucoda, that rely on a post office box rather than rural delivery, the zip code area will reflect the greater rural zip code boundaries and not the localized PO Box zip code. Updated by ECD on 10/10/2016ArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/de74912e711f41f8b559dfc10c97353f_0engThurston GeoData CenterPublicThurston Zip Codes [Washington (State)--Thurston County]Web servicesWashington (State)--Thurston CountyWashington (State)Last Modified: 2025-05-05