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Belmarsh

Reception prisons · HMPPS functional group: Reception · Public sector · Long-term and high-security estate

HMP Belmarsh is a public sector prison in the Reception group. It sits in the lower middle of 31 similar prisons, with a likely position of 12th to 24th. Its official HMPPS rating is "Good". Based on official data to March 2026.

At a glance

Band among 31 reception prisonsLower middle
Likely position 12th to 24th of 31
Median 20th. The range is the 5th to 95th percentile over 1,000 re-weightings and measurement uncertainty.
PillarsSafety Lower middle Decency Upper middle Regime Lower middle Resettlement Bottom quarter
Official HMPPS rating (context)Good, score 63.5%
Not an input to our bands.

The measures behind the bands

Position is where the prison sits among its 31 peers on that measure alone (lower incident rates are better; higher grades and outcomes are better). For incident outcomes the position is after adjusting for who the prison holds.

Fourteen measures in four pillars, each pillar weighted equally.
MeasureThis prisonGroup median Position in groupData from
Safety pillar position: Lower middle
Prisoner-on-prisoner assaults330 per 1,000 prisoners
expected 175
357Bottom quarterApr 2025 to Mar 2026
Assaults on staff178 per 1,000 prisoners
expected 121
140Bottom quarterApr 2025 to Mar 2026
Self-harm incidents604 per 1,000 prisoners
expected 613
686Lower middleApr 2025 to Mar 2026
HMIP healthy prison test: safety3 (reasonably good)2.0Top quarterInspected Jun 2024
Prisoner survey: safety and security4 (highest)3.0Top quarterSurvey from Nov 2024
Decency pillar position: Upper middle
HMIP healthy prison test: respect3 (reasonably good)3.0Upper middleInspected Jun 2024
Prisoner survey: respect33.0Lower middleSurvey from Nov 2024
Regime pillar position: Lower middle
HMIP healthy prison test: purposeful activity1 (poor)1.0Lower middleInspected Jun 2024
Prisoner survey: purposeful activity33.0Lower middleSurvey from Nov 2024
Prisoners in at least half-time purposeful activity40%46%Lower middle2025/26
Resettlement pillar position: Bottom quarter
Housed on the first night after release65%74%Bottom quarter2025/26
In employment six weeks after release9%16%Bottom quarter2025/26
In employment six months after release22%26%Lower middle2025/26
HMIP healthy prison test: preparation for release3 (reasonably good)3.0Upper middleInspected Jun 2024

Incidents compared with what we would expect

Rates are incidents per 1,000 prisoners over April 2025 to March 2026. The expectation is the average of a statistical model of who the prison holds (sentence length, remand, recalls, age, turnover, crowding) and the average of its HMPPS comparator prisons. Neither includes the prison's own result.

OutcomeActualModel expects Similar prisonsExpected (used)Actual ÷ expected Reading
Prisoner-on-prisoner assaults3302591171751.89×Higher than expected on one benchmark only: not flagged
Assaults on staff1781201231211.46×Higher than expected, but within what chance and recording differences could produce
Self-harm incidents6045966306130.99×About as expected

A flag appears only when the result is outside statistical limits and in the same direction under the model, the comparators and their average. It is a prompt to look, not a finding of fault. Counts of one or two incidents are suppressed in the source and estimated here.

Similar prisons

HMPPS names these prisons as the closest comparators, matching on age, sentence length, turnover, sex-offender share, complexity, building age and setting. Rates are per 1,000 prisoners; reoffending is the share of people released in April 2023 to March 2024 who reoffended within a year.

PrisonPrisoner assaultsStaff assaults Self-harmReoffendingOfficial rating
Belmarsh (this prison)33017860444%Good
Long Lartin177215798–Good
Frankland13059.0682–Good
Whitemoor60.7152382–Good
Full Sutton86.152.2657–Good
Wakefield132137632–Good
Average of similar prisons117123630–

Who the prison holds

These describe the population, not the prison's performance. They are what the expectations above adjust for. Averages over the four quarter-ends of 2025/26.

Share of populationThis prison Group median
Average population700904
On remand (untried or convicted, unsentenced)69%59%
Sentence under 12 months1%8%
Sentence 12 months to under 4 years4%9%
Sentence 4 years or more (determinate)9%6%
Life or IPP sentence7%0%
Recalled to custody9%15%
Aged under 2521%16%
Aged 50 or over13%13%
Releases in the year, per prisoner held0.330.83
Prisoners held in crowded accommodation0%56%

Remand is decided by courts and recall by probation and the Parole Board. They are context here, not something a prison controls.

Also shown, not scored

Staff sickness and resignations

Sickness: 12.6 days per full-time employee (HMPPS target 9; median for public prisons in its group 13.3).
Resignation rate: 2.7%.

Position among public-sector prisons in its group: sickness lower middle, resignations lowest quarter. Related to quality in our tests, but the direction of cause is unclear, so it is not scored.

Reoffending after release

44.0% of 277 people released in April 2023 to March 2024 reoffended within a year. Expected given who is released and the mix of the prison and its comparators: 44.6%. Result: about as expected.

The Ministry of Justice says rates by releasing prison should not be used to assess prisons: they do not control for sentence or offender characteristics, and the prison of release may not be where the sentence was mainly served. About two years old.

Disorder incidents and finds

Per 1,000 prisoners, 2025/26This prisonGroup median
Incidents at height50.084.0
Barricades55.815.5
Drug finds330338
Weapon finds242144
Mobile phone finds38.692.7

Not scored. We cannot separate real disorder from differences in how incidents are recorded, and more finds can mean better searching rather than more contraband. Also recorded: 1 release in error; 1 active concerted indiscipline incident; 3 passive concerted indiscipline incidents.

Healthcare (Care Quality Commission)

Provider: Integris Healthcare Partners Limited; Practice Plus Group Health and Rehabilitation Services Limited.
Latest compliance judgement: no compliance judgement published.

The CQC does not give prison healthcare a graded rating, so this is context only.

How current is this?

HMIP gradesInspected Jun 2024
Prisoner survey gradesSurvey from Nov 2024
Incident rates and workforceApril 2025 to March 2026
Resettlement outcomes2025/26 performance year
ReoffendingPeople released April 2023 to March 2024, followed for a year plus a six-month wait for court outcomes
Population mixQuarter-ends June 2025 to March 2026

Sources: data downloads and methodology. Think a figure is wrong? Tell us.