Algonquin is a village in McHenry and Kane counties, Illinois, in the United States. It is a suburb of Chicago, located approximately 40 miles (64 km) northwest of the Loop. As of the 2010 census the village’s population was 30,046, and as of 2017 the estimated population was 31,017.

The village is known as “The Gem of the Fox River Valley”, referring to the location of its downtown. Established in 1890 and long known as a small river community, the village is making the transition into a major regional hub, as it has experienced considerable suburban growth over the past 20 years. Now stretching all the way west to the busy Randall Road corridor, Algonquin has become a major commercial center, with popular shopping centers and restaurants, as well as a growing corporate campus. Additionally, the village continues to see considerable residential growth. With this growth, the village has had to deal with challenges including traffic congestion and overburdened schools, yet has managed to increase the commercial tax base, preserve its character and history, and substantially increase its recreational offerings and quality of life.