Former Michigan State Route 43 is one of the main east-west surface highways in Northern Kalamazoo County. It runs from the Kalamazoo/Van Buren County Line, near Almena, to the Barry/Kalamazoo County Line, near Richland.
In January, 2019, the City of Kalamazoo and the Michigan Department of Transportation reached an agreement to turn jurisdiction of several streets with in Kalamazoo to be turned over to the city jurisdiction from the states. This eliminated BUSN Loop I-94. BUSN U.S. Rt. 131, and Michigan State Route 43 were eliminated within the city. BUSN U.S. Rt. 131 now runs as a short spur on the north of the city. Michigan State Route 43 was rerouted along U.S. Rt. 131 to Michigan State Route 89. BUSN Spur I-94 and Michigan State Route 343 were created to take the numbering of the highways the state retained where the other highways were removed. Former MI St Rt 43 passes through the following towns in Kalamazoo County. Kalamazoo
Richland Former MI St Rt 43 is multi-plexed in Kalamazoo County. BUSN Loop I-94, at Kalamazoo.