In 1961, the rest of old Highway 226 was incorporated into Route 150, continuing south of East Wallingford along Northford Road to Route 17 in Northford. The following year, however, the section of Route 150 east of the current intersection with East Center Street (modern SR 738) was shifted to the current route along Woodhouse Avenue, with the southern terminus set at Route 17 in Northford.
In 1961, the portion of old Highway 226 that is now part of Route 150 extended south from East Wallingford along Northford Road to Route 17 in Northford. The following year, the section of Route 150 east of the current intersection with East Center Street (modern SR 738) was moved to its present route on Woodhouse Avenue, with the southern terminus at Route 17 in Northford.