Buffalo Grove is a village in Lake and Cook counties in the U.S. state of Illinois, within the northwest suburbs of Chicago.
As of the 2010 census, the village population was 41,496. Most of the village is located within the 10th Congressional District of Illinois, although the southern portion is represented in the 8th Congressional District.
Buffalo Grove is located at 42°9′59″N 87°57′48″W (42.166332, −87.963391), among the northwest suburbs of Chicago. Illinois Route 83 leads north towards central Lake County and south towards O'Hare International Airport. East-west streets can take residents east to Lake Michigan and other North Shore suburbs such as Lake Forest, Highland Park, and Glencoe.
Buffalo Grove is about 30 miles (48 km) northwest of the Chicago Loop.
Buffalo Grove is split along Lake Cook Road into two parts: the Lake County Vernon Township portion; and the Cook County Wheeling Township portion. Around three-quarters of the village is in Vernon Township. Both portions differ in their demographics and similarities with neighboring communities. Buffalo Grove shares a border with Wheeling to its southeast, Arlington Heights to its southwest and south, Riverwoods and Deerfield directly east, Lincolnshire to its northeast, Vernon Hills directly north, and Long Grove to its west and northwest. Unincorporated Prairie View is located in two different parts around the village.