Route 220 begins as Elm Street at an intersection with US 5 in the Thompsonville section of the town of Enfield.

It heads east, intersecting I-91 (at exit 48) after 0.4 miles (0.64 km) near Enfield Square Mall.

In the vicinity of the state correctional facility, Route 220 turns north along Taylor Road.

Route 220 runs for another 1.4 miles (2.3 km) to the Massachusetts state line at East Longmeadow.

However, in 1963, the decision was reversed and Route 220 remained intact with an additional westward extension along Elm Street to US 5.