State Trunk Highway 55 is a state highway in Wisconsin, United States. It travels south-to-north in the northeastern part of Wisconsin from an intersection with U.S. Route 151 (US 151) approximately 1.5 miles (2.4 km) north of Brothertown, near the eastern shore of Lake Winnebago in Calumet County, to the Michigan state line at the Brule River approximately one mile (1.6 km) northeast of Nelma in Forest County, where it connects to M-73.

U.S. Highway 151 (US 151) is a United States Numbered Highway that runs through the states of Iowa and Wisconsin. The southern terminus for US 151 is at a junction with Interstate 80 (I-80) in Iowa County, Iowa, and its northern terminus is at Manitowoc, Wisconsin. The route, from south to north follows a northeasterly path through the two states.