Route 75 begins as Poquonock Avenue at Route 159 in the town center of Windsor near the Windsor railroad station and heads northwest parallel to the Farmington River. It has an interchange with I-91 at Exit 38 about northwest of Route 159, where Route 75 also passes in front of Day Hill Mall. After another , Route 75 crosses over the Farmington River into the village of Poquonock, and then has an interchange with the Bradley Airport Connector at the Windsor-Windsor Locks town line.