Allendale Charter Township is a charter township of Ottawa County in the U.S. state of Michigan. As of the 2010 census, the township population was 20,708. It is a part of the Grand Rapids metropolitan area and is an exurb of Grand Rapids due to its major commuter routes into the city (M-45 and I-96).

Allendale is located in the center of Ottawa County, bordered by Tallmadge Township, Polkton Township (City of Coopersville), Robinson Township, Blendon Township and Georgetown Township.

Allendale Charter Township is best known as being home to the main campus of Grand Valley State University.