Warren Hill has been both a juvenile establishment and an adult category C male offenders’ prison. In September 2014 it assumed its current role of a category C men’s prison for those on indeterminate sentences with a history of failing in open conditions or absconding; this group of prisoners are no longer eligible for open conditions or temporary release. Warren Hill is classed as a NOMS national resource.
In addition, the prison has a democratic therapeutic community (TC) that was separate from the progression regime; it had moved to Warren Hill in February 2014 from HMP Blundeston via for a short period of time HMP Norwich
- Alder: 90-bed unit accommodating category C progression regime prisoners and the temporary segregation unit
- Oak: 95-bed unit accommodating category C progression regime prisoners
- Elm: Democratic TC accommodating 40 up-to prisoners – all prisoners undertake core therapy Monday to Friday
- Maple: 20-bed PIPE accommodating prisoners who have completed intensive therapy Sycamore: 12-bed older prisoners’ unit housing progression regime prisoners (closed due to site- improvement work)
- Beech: Segregation unit (closed due to site-improvement work).