WIS 33 begins 300 feet (91 m) east of the Mississippi River where it intersects U.S. Highway 14 (US 14) and US 61 just south of downtown La Crosse.

It runs concurrently with WIS 162 from Newberg Corners to Middle Ridge.

Then, it briefly runs concurrently with WIS 131 in Ontario, then briefly meanders south through the Wildcat Mountain State Park, and then meanders back east.

Just north of West Baraboo, WIS 33 joins US 12 southward at a dumbbell interchange.

As WIS 136 leaves southward at a four-way intersection, Business US 12 joins in from the north.

[2] As WIS 33 continues eastward, it then meets I-90/I-94 at a parclo north of the Cascade Mountain ski resort.

In Beaver Dam, WIS 33 turns east, briefly following Business US 151.

Continuing east, it ends in downtown Port Washington at WIS 32 one mile (1.6 km) west of Lake Michigan.

The portion of the route from Union Center to Camp Douglas became WIS 94.