The Jack County Courthouse, at 100 N. Main St. in Jacksboro, Texas, was completed in 1940. It was designed in 1939 by Wichita Falls architects Voelker & Dixon. It was listed on the National Register of Historic Places in 2012. The courthouse is the fourth courthouse building to have served the county. It replaced an 1885 courthouse. The first courthouse was established in 1858 in an already-existing wooden building on the west side of the Jacksboro town square, which was remodeled at cost of $800.