Elgin is a city in Cook and Kane counties in the U.S. state of Illinois. It is located 35 mi (56 km) northwest of Chicago along the Fox River. As of the 2020 census, the city had a population of 114,797, making it the sixth-most populous city in the state.

Kane County is a county in the U.S. state of Illinois. According to the 2020 census, it has a population of 516,522, making it the fifth-most populous county in Illinois. Its county seat is Geneva, and its largest city is Aurora. Kane County is one of the collar counties of the metropolitan statistical area designated "Chicago–Naperville–Elgin, IL–IN–WI" by the US census.