Additional data
Additional information on the safe, decent and secure running of the prison service.
Visit prisons and probation statistics for data sources and more details.
Annual prison performance ratings
Prison level performance is monitored and measured using the Prison Performance Tool Dashboard (PPTD). In in 2023/24 this provided a data-informed assessment of performance in each prison to derive overall prison performance ratings.
In the PPTD, overall performance is rated as either: Outstanding performance, Good performance, Performance of concern, or Performance of serious concern.
Values:
- 4 - Outstanding performance: 12 prisons
- 3 - Good performance: 48 prisons
- 2 - Performance of concern: 37 prisons
- 1 - Performance of serious concern: 22 prisons
For the source of this information and more details please refer to the publication: Prison performance ratings (annual)
Published: 31 July 2025.
1 - Performance of serious concern
Crowding
Percentage of prisoners held in crowded accommodation.
Prison crowding statistics use automated monthly data from 2024-25, providing a more reliable and accurate calculation of crowding levels compared with the previous manual monthly returns. This change does not materially impact the levels of crowding at a national level, however, the automated process has enabled corrections in reporting at prison level, resulting in some increases/decreases at a small number of prisons. For this reason, no comparisons have been made with previous years' crowding data.
Apr 2024 to Mar 2025
24.8%
Data source
The data source for this measure and more detailed information can be found in the HM Prison and Probation Service annual digest publication.
Publication date
Published: 31 July 2025.
Historic crowding data from 1998 to 2024
Percentage of prisoners held in crowded accommodation.
Prison crowding statistics use automated monthly data from 2024-25, providing a more reliable and accurate calculation of crowding levels compared with the previous manual monthly returns.
| Period | Historic crowding data from 1998 to 2024 |
|---|---|
| Apr 1998 to Mar 2099 | 20.0% |
| Apr 1999 to Mar 2000 | 20.1% |
| Apr 2000 to Mar 2001 | 18.2% |
| Apr 2001 to Mar 2002 | 19.2% |
| Apr 2002 to Mar 2003 | 23.3% |
| Apr 2003 to Mar 2004 | 24.8% |
| Apr 2004 to Mar 2005 | 24.3% |
| Apr 2005 to Mar 2006 | 24.0% |
| Apr 2006 to Mar 2007 | 24.6% |
| Apr 2007 to Mar 2008 | 25.3% |
| Apr 2008 to Mar 2009 | 25.3% |
| Apr 2009 to Mar 2010 | 24.6% |
| Apr 2010 to Mar 2011 | 24.2% |
| Apr 2011 to Mar 2012 | 25.1% |
| Apr 2012 to Mar 2013 | 23.9% |
| Apr 2013 to Mar 2014 | 24.1% |
| Apr 2014 to Mar 2015 | 25.5% |
| Apr 2015 to Mar 2016 | 24.5% |
| Apr 2016 to Mar 2017 | 24.5% |
| Apr 2017 to Mar 2018 | 24.2% |
| Apr 2018 to Mar 2019 | 22.5% |
| Apr 2019 to Mar 2020 | 22.5% |
| Apr 2020 to Mar 2021 | 20.2% |
| Apr 2021 to Mar 2022 | 20.6% |
| Apr 2022 to Mar 2023 | 22.9% |
| Apr 2023 to Mar 2024 | 23.6% |
Apr 2023 to Mar 2024
23.6%
Data source
The data source for this measure and more detailed information can be found in the HM Prison and Probation Service annual digest publication.
Publication date
Published: 31 July 2025.
Releases in error
A prisoner is released in error if they are wrongly discharged from a prison or court when they should have remained in custody, where the prisoner has not deliberately played a part in the error (i.e. the prisoner had no intent of escaping).
Examples include misplaced warrants for imprisonment or remand, recall notices not acted upon, sentence miscalculation or discharging the wrong person on escort.
The rise in releases in error in 2024-25 is believed to be linked to the requirement on Offender Management Units to digest and implement a range of operational and legislative changes. The rise in this year also partly reflects a number of offenders who were released in error in the first tranche of SDS40 due to an issue with a repealed Breach of Restraining Order offence, which was swiftly identified and corrected with legislation. These offenders were all rearrested and returned to custody.
Some releases in error incidents are only identified after the end of the reporting period for the financial year and so haven't previously been included within the published statistics. In this publication we have additionally reported those release in error incidents that were reported after the end of the reporting period, from April 2022 onwards.
| Period | Releases in error |
|---|---|
| Apr 2006 to Mar 2007 | 52 |
| Apr 2007 to Mar 2008 | 31 |
| Apr 2008 to Mar 2009 | 63 |
| Apr 2009 to Mar 2010 | 68 |
| Apr 2010 to Mar 2011 | 63 |
| Apr 2011 to Mar 2012 | 42 |
| Apr 2012 to Mar 2013 | 44 |
| Apr 2013 to Mar 2014 | 50 |
| Apr 2014 to Mar 2015 | 49 |
| Apr 2015 to Mar 2016 | 64 |
| Apr 2016 to Mar 2017 | 72 |
| Apr 2017 to Mar 2018 | 66 |
| Apr 2018 to Mar 2019 | 64 |
| Apr 2019 to Mar 2020 | 50 |
| Apr 2020 to Mar 2021 | 46 |
| Apr 2021 to Mar 2022 | 54 |
| Apr 2022 to Mar 2023 | 81 |
| Apr 2023 to Mar 2024 | 115 |
| Apr 2024 to Mar 2025 | 262 |
Apr 2024 to Mar 2025
262
Data source
The data source for this measure and more detailed information can be found in the HM Prison and Probation Service annual digest publication.
Publication date
Published: 31 July 2025.
Prison staff in post (bands 3-5)
The chart shows Band 3-5 prison officer staff (full time equivalent) at the end of each financial year.
| Period | Prison staff in post (bands 3-5) |
|---|---|
| March 2010 | 24,830 |
| March 2011 | 24,369 |
| March 2012 | 22,735 |
| March 2013 | 21,506 |
| March 2014 | 18,251 |
| March 2015 | 18,222 |
| March 2016 | 18,327 |
| March 2017 | 18,359 |
| March 2018 | 21,007 |
| March 2019 | 22,594 |
| March 2020 | 21,884 |
| March 2021 | 21,863 |
| March 2022 | 21,921 |
| March 2023 | 22,202 |
| March 2024 | 23,590 |
| March 2025 | 22,716 |
March 2025
22,716
Update 30-Jun-2025
At 30 Jun 2025 there were 22,702 Band 3-5 FTE officers in post.
Data source
The data source for this measure and more detailed information can be found in the HM Prison & Probation Service workforce quarterly publication.
Publication date
Published: 21 August 2025. Next publication: 20 November 2025 9:30am. Update expected here by 15 December 2025.
Staff sickness (prisons)
Sickness absence (average working days lost per FTE staff) for operational grade staff.
| Period | Staff sickness (prisons) |
|---|---|
| Apr 2009 to Mar 2010 | 11.6 days |
| Apr 2010 to Mar 2011 | 10.5 days |
| Apr 2011 to Mar 2012 | 10.7 days |
| Apr 2012 to Mar 2013 | 11.2 days |
| Apr 2013 to Mar 2014 | 11.9 days |
| Apr 2014 to Mar 2015 | 12.1 days |
| Apr 2015 to Mar 2016 | 11.1 days |
| Apr 2016 to Mar 2017 | 10.8 days |
| Apr 2017 to Mar 2018 | 9.7 days |
| Apr 2018 to Mar 2019 | 9.9 days |
| Apr 2019 to Mar 2020 | 11.1 days |
| Apr 2020 to Mar 2021 | 13.4 days |
| Apr 2021 to Mar 2022 | 15.9 days |
| Apr 2022 to Mar 2023 | 14.2 days |
| Apr 2023 to Mar 2024 | 11.7 days |
| Apr 2024 to Mar 2025 | 12.5 days |
Apr 2024 to Mar 2025
12.5 days
Update 30-Jun-2025
For the 12 months to 30 Jun 2025 there were an average of 12.9 working days lost to sickness for operational grade staff.
Data source
The data source for this measure and more detailed information can be found in the HM Prison & Probation Service workforce quarterly publication.
Publication date
Published: 21 August 2025. Next publication: 20 November 2025 9:30am. Update expected here by 15 December 2025.