Allendale is a village located in Wabash County, in the state of Illinois (IL), United States. Nestled in the East North Central division of the Midwest region, it covers an area of 0.3 square miles (1.0 km²) and sits at an elevation of 500 ft. With a population of approximately 528 residents, Allendale offers a peaceful, rural atmosphere.
The town's population is composed of about 49.62% males and 50.38% females, and it has a population density of 760.00 people per square mile (679.54/km²). Allendale lies at a latitude of 38.53 and a longitude of -87.71, operating in the UTC-6.
Locals reflect a blend of American ancestry, with roots primarily in United States (16.5%), followed by English (11.6%), German (20.6%), and Scotch-Irish (0%) heritage. The town is identified by the ZIP code 62410.