UK Prison Population Statistics

This briefing paper explores data on the UK prison population, including the population size and change over time, the demographic profile of prisoners, safety in prisons, and the cost per prisoner.

Prisons are devolved, so UK prison statistics are published separately for England and Wales (the Ministry of Justice), Scotland (the Scottish Government), and Northern Ireland (the Department of Justice). This briefing also compares the UK with other countries.

Prison population

Weekly prison population data are available for England, Wales and Scotland and quarterly data are available for Northern Ireland. As of June 2021, the UK had a total prison population of approximately 87,550 people, comprising

• 78,756 in England and Wales,
• 7,417 in Scotland, and
• 1,377 in Northern Ireland (average daily prison population for the financial year 2020/21).

The prison population has fallen since lockdown measures were introduced in response to the Covid-19 pandemic. Since the end of February, the UK prison population has shrunk by around 5,500 people or 6%.

In addition to these snapshots, all jurisdictions publish the average annual prison population, which was approximately 80,366 in England and Wales in the 2020, and 8,198 in Scotland in 2019/20 and 1,448 in Northern Ireland in 2020/21.

Change over time

There is a general underlying, increasing trend in the number of people held in prison. The graph below shows prison population change relative to 1900 (and relative to 2000 for Northern Ireland).

The prison population of England & Wales quadrupled in size between 1900 and 2018, with around half of this increase taking place since 1990.  The Scottish prison population almost doubled in size since 1900 and rose 60% since 1990.

The data series for Northern Ireland begins in 2000. Between 2000 and 2020/21 the prison population of Northern Ireland increased by 36%, although the prison population is currently lower than at its peak of around 1,800 in 2014.

Prison population per capita

To put the prison population in context, it is possible to calculate the number of prisoners per 100,000 people in the general population. At the most recent count, there were:

• 167 prisoners per 100,000 of the population in England and Wales (2020)
• 178 per 100,000 in Scotland (2020), and
• 96 per 100,000 in Northern Ireland (2020/21).

Projections

In each jurisdiction, prison population projections are made on a regular basis. At the most recent estimate, the prison population in England and Wales is projected to grow to 98,700 by 2026, to 7,800 in Scotland by 2022, and to 2,251 in Northern Ireland by 2022.

Further statistics

The availability of more detailed data on the prison population varies by jurisdiction. Where available, this briefing contains statistics on:

• Sentence length and offences for which prisoners were convicted
• Age of prisoners
• Nationality
• Ethnicity and religion
• Over-crowding
• Safety in prisons (assault, self-harming, deaths in prison, drugs)
• Prisoner escapes and absconds
• Cost per prisoner

An Excel spreadsheet is also provided which contains the underlying data to the charts in the briefing.