M-43 (Michigan Highway)

M-43 (Michigan Highway)

M-43 is a state trunkline highway in southwestern and central parts of the US state of Michigan. The highway runs from South Haven to Webberville along an indirect path through both rural areas and larger cities. The trunkline follows three overall segments: a southeasterly track from South Haven to Kalamazoo, a northeasterly course to the Hastings area and an easterly route through the Lansing area.

The M-43 designation dates back to at least July 1, 1919, when it was used on a series of roadways running between Kalamazoo and St. Charles. Its northern- and easternmost sections were transferred to other highways in the 1930s. Additions to M-43 extended it to its current termini. Several sections of the highway were realigned during its history, one of these changes led to the creation of a business loop in Grand Ledge. Another former segment of the trunkline in the Lansing area has been renumbered M-143.