HMP Belmarsh continues to grapple with serious challenges as population pressures intensify

A rise in the number of young adults at high security HMP Belmarsh is taking a toll on staff and other prisoners, according to the prison’s Independent Monitoring Board (IMB) in its annual report, published on the 29 of November 2025. 

The Board notes that:

• HMP Belmarsh is not sufficiently resourced to be a suitable location for young people, and the Board is particularly concerned about the lack of purposeful activity for Category A 18-21 year olds, and the negative impact this has on their mental health and general well-being
• There was a 14% rise in incidents of violence, and violence was most frequent in the young adult age group (18-25 years old). This was accompanied by a 22% increase in the number of weapons found in the prison.
• The rise in the number of prisoners with mental illness awaiting a secure hospital place, and the number of high-profile Category A prisoners held in the healthcare in-patient unit, meant several very unwell patients had to be accommodated with the rest of the prison population.
• The 28-day target for transfer of the most severe mentally ill prisoners to a secure hospital is routinely missed, with prisoners waiting an average of 80 days for a placement.

However, members of the IMB praised:

• Staff and senior leaders for their dedication and positive attitude in meeting the day-to-day challenges presented by a prison running at, or close to, capacity.
• The efforts made to improve the provision of purposeful activities and employment opportunities for prisoners, although there were only workspaces for half the prison’s population.
• The efforts made to reduce the number of prisoners with addiction issues through the introduction of a substance free living wing. The results of mandatory drug tests and the fall in drug finds suggest that Belmarsh has been one of the most successful prisons in the estate at controlling the entry of illicit substances.

Belmarsh IMB Chair, Peter Ward, said

“Like many prisons across the estate, Belmarsh faced significant challenges this year due to the large number of violent incidents and the complex prisoners it was required to house, many of whom would be better placed elsewhere. In particular, the growing number of young adults under 25 put a significant strain on resources, making the management of this cohort increasingly demanding.”