Public Figures

Britain’s official statistics

Prison population and capacity

Dartmoor · August 2026

Dartmoor prison had no accommodation in use in August 2026, and held no one.

Read from the Ministry of Justice’s August 2026 bulletin, in the vintage we archived on 11 October 2026. The count was taken on 24 August 2026.

Dartmoor was published with no accommodation in use in August 2026, so there is no crowding figure to calculate. A percentage of zero certified places is not a number, and we would rather show nothing than invent one.

The fullest establishments in August 2026

  1. 1stLeeds167%
  2. 2ndDurham166%
  3. 3rdWandsworth164%
  4. 4thPreston159%
  5. 5thSwansea156%
  6. 6thExeter156%
  7. 7thDoncaster152%
  8. 8thAltcourse143%
  9. 9thCardiff140%
  10. 10thHull140%
  11. out of 120 establishments with accommodation in use

Population divided by in-use certified normal accommodation, for every establishment in the same bulletin. Establishments with no accommodation in use have no percentage and are left out of the ranking rather than placed at either end of it.

Every month we hold for Dartmoor

Mar 20186%–107% across 77 readings on recordJul 2024

One cell per month from Mar 2018 to Jul 2024, shaded from this establishment’s own emptiest month to its fullest. The record starts in March 2018 because that is the first bulletin published as a spreadsheet; earlier months exist only as word-processor files we will not guess at.

The last twelve months

MonthPopulationIn-use CNAFull
Aug 202600—
Jul 202600—
Jun 202600—
May 202600—
Apr 202600—
Mar 202600—
Feb 202600—
Jan 202600—
Dec 202500—
Nov 202500—
Oct 202500—
Sep 202500—

What the bulletin publishes, and what it means

Baseline CNA640
The sum total of all certified accommodation in an establishment, except normally cells in punishment or segregation units and healthcare cells not used for long-stay patients.
In-use CNA0
Baseline CNA less those places not available for immediate use — damaged cells, cells affected by building works.
Operational capacity0
The total number of prisoners an establishment can hold without serious risk to good order, security and the proper running of the planned regime. Determined by Prison Group Directors on the basis of operational judgement and experience.
Population0
The number of people held. The publisher notes that the prison unlock figure may be lower, as the population includes prisoners on authorised absence.

The publisher’s own definitions, quoted from the bulletin. We divide the population by in-use CNA rather than by operational capacity: operational capacity is what an establishment can be pushed to hold, in-use CNA is what it was certified to hold decently, and dividing by the larger of the two flatters every prison in the estate.