HMP Guys Marsh

From field hospital to adult training prison

In shortGuys Marsh began as a World War II field hospital and has been a fully adult category C training and resettlement prison since 2004.

It is a category C training and resettlement prison for adult men near Shaftesbury in Dorset, built mainly in the 1970s and 1980s as a campus-style institution. The HMPPS recruitment page describes the prison as sitting in a rural area about two miles from Shaftesbury, and says it provides education, vocational training and rehabilitation programmes.

• A large modern block holding the education area, chaplaincy rooms, library and health care department (IMB).
• A small range of workshops and land-based activities including horticulture and grounds maintenance.
• A visitors’ centre just outside the perimeter fence.

Capacity, units and the expansion programme

In shortGuys Marsh held 480 men at the January 2025 inspection, and a stalled expansion for a further 180 prisoners was resumed under Kier in early 2025.

• Held, January 2025480Operational capacity 487, temporarily reduced from 511 because of building work
• Serving four years or more66%
• Serving IPP sentences60Half were receiving support for substance misuse
• Planned extra places180Subject to re-pricing and business case approval

HMPPS’s monthly figures for 24 August 2026 show 444 prisoners against an operational capacity of 445.

The IMB’s report for 1 December 2024 to 30 November 2025, published in April 2026, says an expansion programme begun in early 2022 stalled when the main contractor, ISG, went into administration in September 2024, and that Kier was chosen to resume it in early 2025.

A separate project to replace the district heating main was awarded to Kier.

Anglia

Induction.

Mercia, Saxon, Gwent and Dorset

General population.

Jubilee

Enhanced.

Cambria

Drug recovery wing.

Rainbow

En-suite pod unit, closed for construction.

Tarrant

Segregation unit.

What inspectors found in January 2025

In shortHMIP rated safety and respect poor and called it a ‘concerning report’, with 15 key concerns, eight of them priorities.

• SafetyPoor
• RespectPoorReasonably good in 2022
• Purposeful activityNot sufficiently good
• Preparation for releaseNot sufficiently good

HMIP inspected on 6 to 16 January 2025 and published its report on 15 April 2025.

The Chief Inspector wrote that the prison had deteriorated further and reported that about a third of prisoners said they felt unsafe, 63% said drugs were easy to get and about 30% of prisoners were locked in their cells during the working day.

The November 2025 review of progress

In shortHMIP’s review found good progress on one concern, reasonable on three and insufficient on four, with staffing the most explicit problem.

• Good progress1
• Reasonable progress3
• Insufficient progress4
• Staff available for operational duties60% to 80%Enough to deliver a full regime

HMIP returned for an Independent Review of Progress on 3 to 5 November 2025 and published its report on 8 December 2025. Violence had fallen by about a third, supported by a more consistent regime with incentives, better staff-prisoner relationships and improved living conditions, and health care was better structured.

Illicit drugs, however, remained a serious threat, and enhanced gate security was still lacking. Ofsted found reasonable progress on three of four themes and said waiting lists for English and maths had been eliminated.

• There were now fewer Band 3 officers in post than at the full inspection.
• The national pipeline for appointing and allocating officers was ineffective, and new officers promised to the prison often did not arrive.
• Leaders could no longer rely on recruitment from Commonwealth countries following Home Office changes to immigration rules and had already lost three such staff.
• There were still too few staff to carry out all tasks, including suspicion drug testing.

What the IMB reported for 2024-25

In shortThe IMB recognised the governor’s efforts and falling violence and self-harm, while agreeing that illicit drugs remain a serious threat.

The IMB said weak leadership remained a concern on some wings where inexperienced staff lacked direction, that managerial presence had improved but was inconsistent, and that it hoped a national management and workforce development initiative, Project Enable, would help.

Working at Guys Marsh

In shortHMPPS advertises officer pay of £34,928 to £39,334 on an undated page, so check the live advert; Guys Marsh is in the national pay zone with no supplement.

• Advertised officer pay£34,928 to £39,334On a 37 to 41-hour contract; the page is undated
• Band 3 to 5 officers (FTE), 30 June 2026128Full-time-equivalent Band 3 to 5 officers against a target of 150
• HMPPS performance rating2 of 42025/26; overall score 53.2%

HMPPS runs a dedicated recruitment page for prison officers at Guys Marsh. It says officers work varied shifts including unsocial hours and public holidays, receive mentoring and two weeks shadowing experienced staff, and are supported through a one-year probation, with specialisms available in security, search teams, offender management or dog handling.

It states that officers ‘earn between £34,928 and £39,334’ on a 37 to 41-hour contract, depending on training and chosen hours; the page is undated, so check the live advert for current figures against our pay page and the prison officer pay bands guide.

• The page says the prison is about two miles from Shaftesbury, with free on-site parking, and that Warminster, Frome, Salisbury and Yeovil are within an hour’s drive.
• The nearest station is Gillingham (Dorset), around five miles away on the page and about six on GOV.UK, with no bus service from the station or from Shaftesbury.
• Guys Marsh is in the national pay zone with no market supplement on the list we checked on 3 October 2026.
• See how to become a prison officer.