| State: | WI |
| Type: | WI |
| Route: | 55 |
| Map Custom: | yes |
| Map Notes: | WIS 55 highlighted in red |
| Length Mi: | 175.55 |
| Length Ref: | [1] |
| Length Round: | 2 |
| Direction A: | South |
| Direction B: | North |
| Terminus A: | in Brothertown |
| Junction: | |
| Terminus B: | in Nelma |
| Counties: | Calumet, Outagamie, Shawano, Menominee, Langlade, Forest |
| Previous Type: | WI |
| Previous Route: | 54 |
| Next Type: | WI |
| Next Route: | 56 |
State Trunk Highway 55 (often called Highway 55, STH-55, or WIS 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. Highway 151 (US 151) approximately 1.5miles north of Brothertown, near the eastern shore of Lake Winnebago in Calumet County, to the Michigan state line at the Brule River approximately 1miles northeast of Nelma in Forest County, where it connects to M-73.
WIS 55 begins at an intersection with US 151 directly across Lake Winnebago from Oshkosh. Proceeding north, it passes through Stockbridge. Just south of Sherwood it merges with WIS 114 and the highway enters Sherwood and turns to go northwest. At a roundabout junction, WIS 55 leaves the concurrency with WIS 114 to go north. It crosses US 10 at another roundabout junction and enters Kaukauna on Lawe Street and crosses the Fox River. Past downtown it turns onto Delanglade Street. WIS 55 crosses Interstate 41 (I-41) and US 41 as it leaves Kaukauna and turns to go north, passing through Freedom. WIS 55 runs concurrently with WIS 54 for one mile before turning to go north, passing through Seymour. As the highway proceeds north, it crosses WIS 156.
WIS 55 joins the WIS 29 expressway and leaves the expressway before entering Shawano. There is a short concurrency with WIS 22. North of Shawano the highway enters the Menominee Indian Reservation. North of the reservation it crosses WIS 64 and proceeds north through the forest. WIS 55 runs concurrently with US 8 in Crandon. As it leaves Crandon it runs concurrently with WIS 32 until Argonne, where WIS 32 turns to go northwest toward Three Lakes. WIS 55 enters the Headwaters Wilderness.
In the forest, the highway crosses WIS 70 and goes through the town of Alvin and terminates at the Wisconsin-Michigan border on a bridge over the Brule River, where it continues as M-73.
The original bridge over the Brule River was built in 1922. In a joint project with the Michigan Department of Transportation (MDOT), the Wisconsin Department of Transportation (WisDOT) funded a replacement in 2003. WisDOT supervised the construction of the new span in a project that ran between July 14 and November 4, 2003.[2]
A new roundabout was opened at the intersection of WIS 55 and US 10 between Sherwood and Kaukauna in the autumn of 2009.Another roundabout recently opened at the busy intersection of WIS 55 and WIS 114 approximately 1miles west of Sherwood, Wisconsin.
Over the summer of 2018, a 1spell=inNaNspell=in section of WIS 55 at its interchange with I-41 in Kaukauna was reconstructed and four new roundabouts were added.[3]
In summer of 2023, the shoulder was widened in Alvin for bicycle access as part of a resurfacing project.