Boise is associated with which airport code?

Boise is indeed associated with the airport code BOI. This three-letter code is designated by the International Civil Aviation Organization (ICAO) and the International Air Transport Association (IATA) to uniquely identify Boise Airport, which serves as the primary airport for the city of Boise, Idaho.

Each airport code typically corresponds to the city's name or its significant geographical features to ensure easy recognition for travelers and those in the aviation industry. In this case, "BOI" retains a clear relationship to the name of Boise, making it an effective identification for this airport. The other codes listed refer to different airports not associated with Boise: BIL is for Billings, Montana; BMI is for Bloomington, Illinois; and BHM is for Birmingham, Alabama.