M-30 (Michigan highway)

M-30 is a state trunkline highway in the U.S. state of Michigan that runs in a north–south direction from M-46 near Merrill to M-55 in West Branch. The highway runs through rural parts of five counties in the Lower Peninsula. The southern end runs along the Michigan Meridian and parallel to the Tittabawassee River. The southern end of the highway has been truncated twice and re-extended twice back to its pre-1962 extent.

Prior to 1962, M-30's southern terminus was at the junction with M-46 in Merrill. Since then, the segment south of US Highway 10 (US 10) was returned to local control and decommissioned as a state highway. In May 2009, M-30 was extended southerly from US 10 to M-20, restoring some of the highway decommissioned in the 1960s to M-30. It was then extended back to M-46 in 2022.