The remainder of NY 37's old routing through Massena became an extension of NY 37B, which continued west through the town of Louisville on Town Line Road and an unnamed roadway along the St. Lawrence River to NY 37 at Louisville Corner.
The original path of NY 37 through Massena was replaced by a new route that extended NY 37B westward, using Town Line Road and an unnamed road along the St. Lawrence River to rejoin NY 37 at Louisville Corner.