An average of 297 prisoners were incarcerated at Castlerea jail every day last year.
The Irish prison service annual report reveals that the prison has capacity for 340 normally.
On average 14 prisoners were on temporary release from Castlerea with 57 inmates on remand waiting for trial at the Roscommon jail last year.
The prisoner peer mediation scheme which is operated at Castlerea also awarded certs to four prisoners last year as part of a programme that focused on the reduction of violence within prisons and, consequently, in the community.