Projection falling

In the central scenario, by September 2028, the total prison population is now estimated to be around 2,400 lower than in the previous 2024 to 2029 publication. The difference is predominantly driven by the impact of recent sentencing policy measures including:

• The impacts of The Criminal Justice Act 2003 (Home Detention Curfew) Order 2023 and changes to the Home Detention Curfew (HDC) policy framework which increased the time offenders could spend on HDC to a maximum of 12 months (implemented 3rd June 2025)
• The Criminal Justice Act 2003 (Suitability for Fixed Term Recall) Order 2025 which increased use of Fixed Term Recall for offenders on sentences of under 4 years.

Uncertainty

In the first few years of the projection period, the projected rise in the prison population is heavily influenced by an increase in receptions of determinate sentenced offenders. This increase in receptions reflects observed increases in police and prosecutorial activity over recent years, leading to projected increases in the number of cases that enter the criminal courts.

There are several sources of uncertainty in projecting the future prison population, particularly around the level of demand entering the Criminal Justice System (CJS). This publication presents three prison population projections to assess the impact of differing possible upstream demand scenarios which have been agreed between the Ministry of Justice (MoJ), the Home Office and the Crown Prosecution Service (CPS).

The cross-CJS view is that charge volumes are likely to continue rising over a three-to-five-year horizon. Although there are factors such as a growth in police officer workload which could supress charge volumes, these are assumed to be outweighed by charge increasing factors such as: increases in officer experience; officer numbers and investigator capacity. It is on this premise that the following scenarios are estimated:

• Low upstream demand: assumes demand remains at the level observed in the 12 months to Jun-25.

• Central upstream demand: assumes that demand continues to rise but at a gradually decreasing rate. Demand at March 2030 is c.7% and c.9% higher in Crown and magistrates’ courts respectively than the level observed in the 12 months to Jun-25.

• High upstream demand: reflects the fact that there are several risks that could drive demand up further than the ‘Central’ estimate. The ‘High’ scenario reflects a situation where current growth rates continue for a further 12 months before starting to level off. Demand at March 2030 is c.13% and c.14% higher in Crown and magistrates’ courts respectively than the level observed in the 12 months to Jun-25.

Continued growth in number of older prisoners

Over the course of 2025 the proportion of the prison population aged 50 and older has remained relatively flat at c.18%. The 50-year-old and over population is projected to increase from 16,163 at the end of September 2025 to 18,600 in September 2029 in the central scenario.

This projected increase in the 50-year-old and over prison population is driven by the same underlying drivers as those in the overall population, including growth in police charging and prosecutorial activity and receipts into court.

Age and sex

The adult male (18 and over) population is projected to increase from 83,685 at the end of September 2025 to 95,400 by September 2029. 

The juvenile population includes those in the 15 to 17 age group and covers only offenders held in HMPPS estates. Note that figures do not cover those young offenders held in Secure Children’s Homes or Secure Training Centres. The juvenile population decreased in 2020 and has remained roughly constant at c.300 since the end of 2020. The number of 15- to 17-year-olds in HMPPS custody is projected to remain at this level throughout the projection, with a projected population of c.300 at September 2029.

The adult female population has remained flat since September 2024 and is 3,527 at the end of September 2025 (3,524 at end of September 2024). This population slightly increased over 2025 before decreasing in September 2025 as a result of the recent change to fixed term recalls and is projected to increase to 3,900 in the central scenario by September 2029.

Potential for lower growth

These estimates do not account for future policies that are likely to impact the prison population but are yet to be formally agreed by Parliament. For example, the sentencing reforms as set out in the Sentencing Bill 2025, which are designed to suppress growth in the prison population, are not included, nor are any impacts from government policies in response to the Independent Review into Criminal Courts. Some of the planned measures on the latter such as giving Magistrates powers to sentence people to custody for longer would probably increase the population if implemented.