At the town line, the road changes name to Branford Road and continues northward for about 1.5 miles (2.4 km) until its end at an intersection with Routes 22 and 80 in the town center.

[1] In the 1920s, a route running east from Fair Haven (in New Haven) via the village of Totoket to the town center of North Branford, then southward to the northeastern corner of Branford, was a state highway designated as Highway 135.

[3] The southern end of Route 139 originally used School Ground Road.

In the 1940s, the southern terminus was shifted to use North Branford road instead.

The old alignment became Route 139A, which was removed from the state highway system in 1964.