States Bordering Michigan: Ohio, Indiana, Illinois, Wisconsin

Michigan shares land or water borders with four U.S. states:

• Ohio — South (land/water border in Lake Erie & Maumee Bay)
• Indiana — Southwest (land border)
• Illinois — West (water border across Lake Michigan)
• Wisconsin — Northwest (water border across Lake Michigan & Green Bay; land border at Upper Peninsula)

It also shares an international water border with Ontario, Canada (Lake Superior, St. Marys River, Lake Huron, St. Clair River, Lake St. Clair, Detroit River, Lake Erie). Michigan's two peninsulas give it the longest freshwater coastline in the U.S.