How Many Prisons Are in the UK? 143 in 2026, by Nation

In shortIt depends on what you count: 123 establishments in England and Wales (120 rated units), 17 in Scotland and 3 in Northern Ireland.

The honest answer depends on what you count. The official GOV.UK collection "Prisons in England and Wales" has 123 establishment pages, and we hold 123 matching records, including Dartmoor, which has been temporarily closed since September 2024.

The Scottish Prison Service lists 17 prisons and the Northern Ireland Prison Service runs 3. Adding the three gives 143.

A second figure, 120, appears in HMPPS performance ratings, published 30 July 2026, which rated 120 prisons. That set differs from the GOV.UK list because some sites are reported together and Peterborough's male and female sides are counted separately. Neither number is wrong; they answer different questions.

Use 123 if you mean 'establishments listed by GOV.UK' and 120 if you are quoting performance ratings.

A third complication is whether to count units that are not prisons in the everyday sense: the community custody units in Scotland, young offender institutions and the youth custody estate. Our full UK prisons list shows every one with its type so you can apply your own definition.

In shortThree counting rules explain nearly every discrepancy: joint reporting, sites holding different populations, and time.

Our dataset was compiled on 3 October 2026 from the GOV.UK collection, with each page fetched through the GOV.UK content API.

If you are writing something that needs one number, say 'around 120 prisons in England and Wales' or cite the GOV.UK list of 123 establishments. Do not add Scotland and Northern Ireland to a figure from HMPPS tables without saying so.

1. Joint reporting

HMPPS's monthly population bulletin reports Grendon with Spring Hill, Usk with Prescoed, and for the human resources workforce statistics Hollesley Bay with Warren Hill as one 'Hollesley' unit from June 2026. Merging those sites cuts the count.

2. One site, different populations

HMP & YOI Peterborough holds both men and women in separate sites and is counted as two rated units.

3. Time

Prisons open, close and change operator. Five Wells opened in March 2022, Fosse Way in May 2023 and Millsike in April 2025, while Dartmoor closed temporarily in September 2024. An old 'list of UK prisons' can therefore be wrong even if it was right when written.

In short15 of the 123 establishments are privately operated; private-sector staff are employed by the operator, not HMPPS.

• Privately operated15
• Public108
• OperatorsG4S, Serco, Sodexo, MitieMitie for Millsike

The 15 comprise the HMPPS performance-ratings contracted group plus Millsike, which opened in April 2025.

Private-sector prison staff are employed by the operator, not HMPPS, and HMPPS workforce statistics do not include them. That is why statements such as '22,001 FTE band 3 to 5 officers' refer to public-sector prisons only.

If you are comparing employers, our guide to private prisons and the guide to prison custody officers in private prisons explain the differences.

In shortScotland has 17 establishments and Northern Ireland 3, run by separate prison services; we do not publish their capacities.

We do not publish their capacities because the HMPPS bulletin does not cover them and we have not verified SPS or NIPS equivalents. For pay in those services see Scotland and Northern Ireland.

Scotland

The Scottish Prison Service says it has 16 publicly managed prisons and one run by a private operator under contract: 17 in all, from Barlinnie and Edinburgh to Castle Huntly, Scotland's only open prison. Kilmarnock was Serco-run until it transferred to SPS on 17 March 2024. Our dataset records the private prison as Addiewell, with the operator marked to confirm.

Northern Ireland

3 establishments: Maghaberry (high security, adult men), Magilligan (men with six years or less to serve) and Hydebank Wood College and Women's Prison.

In shortOn 28 September 2026 the population was 87,499 against useable operational capacity of 89,055, leaving headroom of 1,556 places.

• Population87,499Monday 28 September 2026
• Useable operational capacity89,055
• Headroom1,5561,134 adult male, 311 female, 111 YCS
• HDC caseload3,501Home Detention Curfew

The population was made up of 83,819 adult men, 3,407 women and 273 in the Youth Custody Service estate. Useable operational capacity was 89,055 (84,953 adult male, 3,718 female and 384 YCS). Source: HMPPS weekly population bulletin, 28 September 2026.

A year earlier, on 29 September 2025, the population was 87,336, useable capacity 89,437 and headroom 2,101. So the population is almost unchanged over the year, while headroom has fallen by 545 places.

The Ministry of Justice has said adult male prisons are 'at 98% capacity', which is a government statement rather than a bulletin figure; the weekly numbers above imply adult male population of 83,819 against 84,953 useable places.

In shortPrison capacity has three common measures, and crowding is measured separately.

Prison capacity has three common measures.

Certified normal accommodation (CNA)

The 'uncrowded' capacity of a prison. The monthly bulletin for August 2026 shows a baseline CNA of 85,708 and an in-use CNA of 81,616 for the estate.

Operational capacity

The total number of prisoners an establishment can hold taking into account control, security and the proper operation of the planned regime, set by Prison Group Directors.

Useable operational capacity

The sum of operational capacities less the operating margin.

Crowding

Measured separately. The HMPPS Annual Digest 2025-26 (published 30 July 2026) reports that 24% of prisoners were held in crowded conditions in the 12 months to March 2026, compared with 25% the previous year. The digest will not be published from 2026-27, with the data moving to other publications.

In shortThe government says it is delivering 14,000 additional places by 2031; these are government statements about plans, not a count of open prisons.

• Investment (government)£4.7bnMoJ press release, 14 September 2026
• Additional places by 203114,000More than 3,300 delivered since July 2024
• HMP Welland OaksAbout 1,700 placesPublicly run Category B, opening 2029, Wates contract of £713m

In December 2025 the government said about 5,000 places were under construction and that the estate had grown by less than 500 net places in the 14 years to April 2024. These are government statements about plans and progress, not a count of open prisons.

The one wholly new prison announced is HMP Welland Oaks in Leicestershire. An independent review of the prison system in England and Wales opened a call for evidence in July 2026; its outcome had not been published at the time of writing.

Named projects:

• Houseblocks at Channings Wood, Highpoint and Wayland
• Small secure houseblocks at six further prisons
• Rapid Deployment Cells at Wayland, Haverigg, The Mount and Leyhill
• A 245-place houseblock opened at Fosse Way in December 2025
• 152 Rapid Deployment Cell places under construction at Kirklevington Grange, where groundbreaking took place on 10 September 2026

In shortThe estate is not static: new prisons, operator changes, a role change and a temporary closure since 2019.

The estate is not static. According to the HMPPS Safety in Custody tables, Five Wells (March 2022), Fosse Way (May 2023) and Millsike (April 2025) are the recent new prisons. Birmingham returned to the public sector in July 2019 and Lowdham Grange on 1 August 2024.

Cookham Wood young offender institution became an adult male prison in August 2024, and Dartmoor closed temporarily in September 2024.

In the youth estate the Youth Custody Service, launched in April 2017, runs the public young offender institutions Feltham A, Werrington and Wetherby; Parc YOI is a private unit run by G4S according to GOV.UK, and Oakhill is a private secure training centre. Medway Secure Training Centre closed in March 2020.

Our guide to the youth custody estate goes into this part of the estate.

In shortPublic-sector officer numbers are down year on year; we have not found a source that turns the Sentencing Act progression model into staffing numbers.

• Band 3 to 5 officers (FTE)22,001Public-sector prisons, 30 June 2026; down 701 (3.1%) on a year earlier
• Shortfall against target1,82321,727 FTE in post against a target of 23,550
• Leaving rate8.9%Band 3 to 5, 12 months to 30 June 2026

HMPPS workforce statistics at 30 June 2026 show these figures for public-sector prisons.

At the same time the Sentencing Act 2026 introduces a progression model for standard determinate sentences, phased over 10 tranches from October 2026 to June 2027, with about 4,500 modelled first-day releases in total, according to an MoJ report of 30 August 2026.

We have not found a source that turns this into officer numbers, so do not forecast staffing from it. Our guides to prison staffing and attrition and prison officer assault statistics track the verified data.

If you are thinking of joining, the number of prisons matters less than which one is near you. Use the prison finder and our guide to becoming a prison officer, and check the prison officer pay bands for the pay you would receive.