Route 143 is a 24.5-mile-long (39.4 km) west–east state highway in the U.S. state of Massachusetts. Its western terminus is at Route 8 in Hinsdale, at the town's center. Its eastern terminus is at Route 9 near the village of Searsville in Williamsburg. At Worthington, the highway runs concurrently with Route 112 for 0.8 miles (1.3 km), beginning at Worthington Corners. The road is the only state route through the towns of Peru and Chesterfield, and it crosses the Westfield River in Chesterfield.
Route 143 was originally numbered Route 109A in 1930. The route was renumbered to 143 by 1933.