About this data. This site presents Walla Walla County's 2025 certified assessor values and parcel GIS as a public service, for general informational and research use. It is not to be used for commercial purposes, and the underlying data may not be resold or redistributed. Owner information from public records is not, under Washington law, to be used for commercial solicitation. Figures are estimates for reference and may contain errors — for official records, consult the Walla Walla County Assessor.