The Idaho High School Activities Association (IHSAA) oversees high school athletics and activities in the state of Idaho. Idaho high schools are classified in six categories, based on enrollment, for league competition and state playoffs and championships. The IHSAA recognizes twenty specific sports and activities. Schools primarily compete within their own classification for regular season play, but are allowed to play other schools one classification above or below them in most sports.

Classification

IHSAA classifications are based on four-year enrollments (grades 9–12). The classifications for the state's 171 high schools for 2024–26 are:

Historic classifications

Source:

Districts

The six districts correspond to those used by the state's transportation department.

6A Conferences

High Country Conference (6A) - (east) Inland Empire League (6A) - (north) Southern Idaho Conference (6A) - (southwest)

5A Conferences

High Country Conference (5A) - (East-VI) Great Basin Conference - (South Central-IV) Great Basin Conference - (Southeast-V) Inland Empire League (5A) - (North-I & II) Southern Idaho Conference (5A) - (Southwest-III)

4A Conferences

Intermountain League - (north) Mountain Rivers Conference - (east) Sawtooth Central Conference - (south central) Snake River Valley Conference - (southwest) Southeastern Idaho Conference - (southeast)

3A Conferences

Canyon Conference - (south central) Central Idaho League - (north central) Nuclear Conference - (east) Southeastern Idaho Conference - (southeast) Western Idaho Conference - (southwest)

2A Conferences

Snake River Conference - (south central) White Pine League (Div I) - (north central) Western Idaho Conference - (southwest)

1A Conferences

Long Pin Conference - (southwest) Sawtooth Conference - (south central) White Pine League (Div II) - (north central) North Star Conference - (north) Rocky Mountain Conference - (central)

Neighboring states