Iowa 150 begins at a T intersection with US 218 on the southern side of Vinton. US 218 comes up from the south and turns west at the intersection while Iowa 150 begins heading north along C Street. Near downtown, the highway turns to the east for a few blocks. At the Benton County Courthouse, it turns north once again and almost immediately crosses the Cedar River. North of Vinton, the highway passes a small airport surrounded by fields and then curves to the east for a few miles. West of Urbana, it heads back to the north and intersects Interstate 380 (I-380).