Allegan is a somewhat small city located in the state of Michigan. With a population of 5,164 people and five associated neighborhoods, Allegan is the 188th largest community in Michigan. Allegan has an unusually large stock of pre-World War II architecture, making it one of the older and more historic cities.

Being a small city, Allegan does not have a public transit system used by locals to get to and from work.

The percentage of adults in Allegan with college degrees is slightly lower than the national average of 21.84% for all communities. 13.03% of adults in Allegan have a bachelor's degree or advanced degree.

The per capita income in Allegan in 2022 was $23,306, which is low income relative to Michigan and the nation. This equates to an annual income of $93,224 for a family of four. However, Allegan contains both very wealthy and poor people as well.

Allegan is a very ethnically-diverse city. The people who call Allegan home describe themselves as belonging to a variety of racial and ethnic groups. The greatest number of Allegan residents report their race to be White, followed by Black or African-American. Important ancestries of people in Allegan include German, English, European, Irish, and Dutch.

The most common language spoken in Allegan is English. Other important languages spoken here include Polish and Spanish.