State Route 43 (SR 43) is a state route from Cummings Hill Road and Intervale Road in Temple to U.S. Route 2 (US 2) and US 2A in Old Town.

The route is 103 miles (166 km) long.

Route 43 begins at an intersection with Cummings Hill Road and Intervale Road in Temple.

Then it turns northward with State Route 11.

Then the route heads southeast and crosses Interstate 95 and has its eastern end at U.S. Route 2.