Swaleside opened in 1988 with four wings, and over the years 4 more wings have been added. It is located on the Isle of Sheppey, near Eastchurch village.
- A wing – 126 prisoners.
- B wing – 126 prisoners.
- C wing – 126 prisoners.
- D wing – 126 prisoners
- E wing – 120 prisoners., all enhanced and working in the DHL warehouse.
- F wing – 120 prisoners, including those on the ‘Pathways’ programme (for those with a personality disorder)
- G wing – 179 prisoners, induction wing and IDTS
- H wing – 179 prisoners, including the RAPt/drug-free wing
- Segregation unit – 25-bed unit
- Health care unit – 17-bed inpatient unit