New York State Route 103 (NY 103) is a state highway in Schenectady County, New York, in the United States. It runs for just 0.50 miles (0.80 km) from an intersection with NY 5S in the hamlet of Rotterdam Junction to NY 5 in the town of Glenville. In between, the route crosses the Mohawk River at Erie Canal at Lock 9. When it was assigned in the early 1930s, it was the only crossing of the Mohawk River between Pattersonville and downtown Schenectady.