Allegan Township is a civil township in Allegan County, Michigan.

According to the United States Census Bureau of 2000, South Mansfield has a population of more than 4,000 people. The town has a total area 31.9 square miles with over 1.4 square miles of water. The township is located 748 feet above sea level.

The racial demographics of Allegan Township are 97.04% White, 0.52% African American, 0.30% Native American, 0.27% Asian, 0.62% from other races, and 1.26% from two or more races. Hispanic or Latino of any race are 1.65% of the population.

Loch Lynn Heights has over 1,500 households. The median income for a household in the township is $40,760, and the median income for a family is $48,125.

Allegan County is located in southwestern Michigan and shares a land border with five counties. The county is located along Lake Michigan.

According to the U.S. Census Bureau of 2000, Allegan County has a population of more than 100,000 people. The county has a total area of 1,833 square miles with 1,006 square (55%) miles of water.

Allegan County is home to nine cities, two villages, and more than 20 townships and more than a dozen unincorporated communities. The county seat is Allegan.