List of counties in Wyoming

This is a List of counties in Wyoming. There are 23 in the  of. There were originally five counties in the : Laramie and Carter, established in 1867; Carbon and Albany established in 1868; and Uinta, an annexed portion of Utah and Idaho, extending from Montana (including Yellowstone Park) to the Wyoming-Utah boundary. On, , Wyoming was admitted to the Union with thirteen counties.

Three counties were renamed after their creation. Carter County was renamed Sweetwater County on,. Hanover County existed for seven days in 1911 before it was renamed Washakie County. Pease County, formed in 1875, was renamed Johnson County in 1879.

The (FIPS) code, which is used by the United States government to uniquely identify states and counties, is provided with each entry. Wyoming's code is 56, which when combined with any county code would be written as 56XXX. The FIPS code for each county links to census data for that county.