Idaho Maximum Security Institution (IMSI)

View of IMSI from the front drive
IMSI entrance
Mailing Address:
PO Box 51
Boise, ID 83707
Physical Address:
13400 S. Pleasant Valley Rd
Kuna, ID 83634

IMSI opened in November 1989 to confine Idaho's most disruptive offenders.  The facility has an operating capacity of 402 offenders and is located within a double perimeter fence reinforced with razor wire and an electronic detection system.  The population is primarily comprised of close custody and administrative segregation offenders. IMSI also operates the state Secure Mental Health Facility, houses offenders under the sentence of death, and civil commitments. 

Warden: Al Ramirez, IMSI email address:; Phone: 208-338-1635


Visiting schedules are subject to change based on emergency situations.

Please read and be familiar with the Visiting Rules for Offenders and V