Wyoming Tax Records
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This entry was originally written by Dwight A. Radford in Red Book: American State, County, and Town Sources.
The Wyoming State Archives does not have all of the county tax and assessment records. The county assessor and treasurer use their own discretion as to whether their records are sent to the archives. In order to check the records on file at the Wyoming State Archives, the researcher must know the county (or general area) and the years that the ancestor resided in Wyoming. If tax records are not at the archives, they are likely still at the local courthouses.
Wyoming county tax records may be arranged chronologically and then alphabetically by school district. These records include assessment rolls, inventory, and appraisement of personal and real property for tax purposes. The total amount of tax is then apportioned under the various county and state taxes. Tables list name and address, legal description of the real property, value of real and personal property, amount owed for specific taxes, and date paid.
There are Internal Revenue Assessment Lists for Idaho Territory (1865–66), which will include parts of modern-day Wyoming. These are part of RG 58 at the National Archives and they are on microfilm at the FHL.