Accredited official statistics

How many people are detained under immigration powers in the UK?

Published 21 May 2026

Back to ‘Immigration system statistics, year ending March 2026’ contents page.

This release goes up to the year ending (YE) March 2026. The “year ending” period includes the 12 months up to and including the YE month. For example, YE March 2026 includes the 12 months between 1 April 2025 and 31 March 2026.

An individual may be detained under immigration powers under certain circumstances. This includes detention in support of the return of the individual with no legal right to be in the UK. In some cases, individuals may be detained whilst their identity is being established or where there is a risk of absconding.

1. People entering immigration detention

The number of people entering detention increased in the YE March 2026, continuing the upward trend since 2023.

A total of 22,586 people entered immigration detention in the YE March 2026, 7% more than the previous year. This increase continues an upward trend since 2023.

This increase, in part, reflects the use of detention to facilitate increasing numbers of returns from the UK. The increase in detention intake in the latest year coincides with a 13% rise in returns from detention over the same period (see ‘How many people are returned from the UK?’ for more information).

Asylum-related cases entering detention increased by 10% in the latest year. During this period, individuals were being detained under the UK-France agreement, which was signed in August 2025. The increase also results from a number of foreign national offenders (FNOs) in prisons becoming immediately eligible for removal through the Early Removal Scheme (ERS), in most cases facilitated via the detention estate. The ERS was expanded in September 2025, as part of the Sentencing Review; further details can be found in the policy timeline accompanying this release.

Figure 1: People entering immigration detention in the UK, from the YE December 2015 to the YE March 2026

Source: Immigration detention - Det_D01

Figure 1 shows that although the number entering detention has increased since 2023, numbers remain lower than a decade earlier, with people entering detention falling from 32,447 in 2015 to 24,480 in 2019. This is partly linked to changes in the use of detention and greater use of alternatives as a response to the 2016 Stephen Shaw review of detention.

Although the COVID-19 pandemic impacted detention use in 2020 and 2021, the general downward trend in the number of people entering detention continued up to the YE September 2023. This decline occurred against the backdrop of detained individuals more commonly raising issues while in detention (such as asylum or modern slavery claims), combined with ongoing efforts to minimise the use of detention following the Shaw review, with more individuals managed in the community.

Although detention is primarily used to facilitate a return from the UK, in 2021 many entrants were small boat arrivals detained for initial processing on arrival. From 2022, the opening of Manston immigration centre to process small boat arrivals meant these individuals were no longer being held within the wider detention estate for initial processing, leading to a further decline in numbers entering and enabling more to move directly to community-based accommodation following the initial examination and checks.

Albanians represented a fifth (20%) of people entering detention in the YE March 2026.

Albanians remain the most common nationality entering detention (4,427 entries), despite the number of individuals entering detention being 43% below the peak in YE March 2023 (7,743). This decrease may reflect a declining population of Albanians eligible for removal, given the fewer numbers arriving via illegal routes to the UK over the same period (particularly fewer arriving by small boat), shrinking asylum-seeker caseload for initial decisions and declining prison populations of these nationals.

The next most common nationalities entering immigration detention were India (14%) and Brazil (10%). While the number of Indian entries has continued to rise (up 42% from the previous year), the number of Brazilian entries has remained largely unchanged.

2. People in immigration detention

There was a greater number of people held in detention under immigration powers on 31 March 2026 than a year prior, driven by an increase in FNOs detained in prisons.

There were 1,955 people being held in detention (at an immigration detention facility or in prisons under immigration powers) at the end of March 2026, 8% more than on 31 March a year earlier.

While there has been relative stability in numbers held in detention over the last 2 and a half years (see Figure 2), the last 4 quarters have seen some greater fluctuations. These partially reflect reopening of some immigration removal centres and temporary closures for refurbishment.

The vast majority of people detained under immigration powers are held in the detention estate rather than prisons. Historically, the number of FNOs detained in the prison estate had been much higher, ranging between 300 and 700 between the end of 2017 and start of 2023. Reducing the number of FNOs held in prisons, by expediting their removal from the UK, has been a key priority to reduce pressures on prison capacity. On 31 March 2026 there were 220 FNOs detained in prisons, more than double (up 137%) from the previous year – a substantial increase compared to levels since the second half of 2023, which were around 100. For more information on the number of FNOs leaving the detention estate in 2025, see section 3.3.

While many FNOs subject to deportation action are detained in the detention estate and prisons, many are also managed in the community. For data on those managed in the community, see the Immigration Enforcement Transparency statistics.

The total number of foreign nationals held in prison for criminal offences can be found in the latest prison population statistics, published by the Ministry of Justice and HM Prison and Probation Service.

Figure 2: People detained under immigration powers in the UK, on the last day of the quarter, 31 December 2017 to 31 March 2026^1,2

Source: Immigration detention - Det_D02

Notes:

1. The ‘detention estate’ comprises Immigration Removal Centres (IRC), Short-Term Holding Facilities (STHF) and Pre-departure Accommodation (PDA). It is separate to those who are detained under immigration powers in prisons – these are shown separately on the chart.
2. Prisons data from 31 December 2022 includes prisons in England and Wales only.

The number of people in detention is a snapshot relating to a single point in time, therefore, numbers fluctuate daily. If a large number of people entered detention just before the end of a reporting period, the number of people in detention would be higher than if the same people entered a few days later.

3. People leaving immigration detention

3.1 Reasons for leaving immigration detention

Just over half of those leaving detention (51% of leavers) left on immigration bail.

Figure 3 shows that the most common reason for leaving detention in the YE March 2026 was immigration bail, with 11,406 leaving detention for that reason in the latest year. The proportion leaving detention on bail has remained stable over the last 2 years, following a steady fall since the peak in the YE March 2022. Bail has been the most common reason for leaving detention since 2015; prior to 2015 the most common reason for leaving detention was to be returned.

People are bailed for a variety of reasons, including where there is no immediate prospect for their removal from the UK, or while their asylum claim is being considered, if they have made one.

Detained individuals who claim asylum, or raise other claims (for example, modern slavery or human trafficking) or further submissions (for example, appeals) which prevent progress of their removal, may be granted bail into the community. While on bail, individuals are subject to immigration bail conditions while their claims are concluded. If a claim is refused, the individual may depart the country voluntarily or re-enter detention if required to facilitate enforced removal.

Figure 3: People leaving detention by reason for leaving^1,2 from the YE December 2010 to the YE March 2026

Source: Immigration detention - Det_D03

Notes:

1. Other reasons for leaving detention include being sectioned under the Mental Health Act, entering criminal detention, being detained in error and people whose reason for leaving was not available at the time of publication. See the user guide for more details.
2. The legend follows the same order and orientation as the stacks within the chart.

Just under half (44%) of people leaving detention were returned from the UK in the YE March 2026, similar to the proportion a year ago, but higher than the proportion seen in the YE March 2023 (22%).

There were 9,916 cases of people leaving detention to be returned from the UK in the latest year, constituting 44% of total leavers from detention. The number of people who leave detention to be returned has more than doubled over the last 3 years. Enforced returns from detention are the most common type of enforced return and have generally been rising steadily since the pandemic in 2020 and 2021. For more information about this trend, and the reasons behind it, see the ‘How many people are returned from the UK?’ topic.

Reasons for leaving detention are considered on a case-by-case basis and often vary across nationalities. Nationalities featuring prominently in FNO returns, such as Romanian and Polish nationals, had a higher proportion returned on leaving detention (87% and 60% respectively) than leaving on bail in the latest year. Some nationalities who commonly claim asylum, including Indians and Pakistanis, left detention on bail in greater proportions (74% and 75% respectively). This reflects that people are often granted immigration bail whilst their claims are being considered.

Albanians were the most common nationality leaving detention in the YE March 2026 (4,496 or 20% of total leavers). Albanians are prominent across both the FNO and asylum claiming cohorts with a similar number returned from detention and leaving on bail.

For more information about asylum claim statistics, see the ‘How many people claim asylum in the UK?’ topic.

3.2 Length of immigration detention

Two-thirds (67%) of individuals leaving immigration detention in the YE March 2026 had been detained for less than a month, of which two-fifths (42%) were detained for less than a week.

Most people leaving detention in the YE March 2026 were detained for less than one month. Figure 4 shows shorter durations were more common from the YE June 2020 to the YE December 2022, during which time small boat arrivals were undergoing initial processing in the detention estate, and the COVID-19 pandemic disrupted normal detention estate operations.

Those returned from detention in the YE March 2026 were more commonly detained for shorter periods compared to those being bailed with 37% being returned from the UK after spending under a week in detention (71% under a month), compared to 19% of detainees leaving detention under immigration bail within a week (64% under a month).

Longer stays in detention (3 months and over) have ranged between 8% and 10% of numbers leaving over the last 4 years. In the YE March 2026, 8% of people leaving stayed over 3 months.

Figure 4: People leaving immigration detention, by length of detention¹, proportions of rolling annual totals, from the YE December 2010 to the YE March 2026

Source: Immigration detention - Det_D03

Notes:

1. Month duration refers to a period of 30 days.

3.3 Foreign National Offenders (FNOs) leaving detention

Data on FNOs leaving detention is classified as ‘official statistics in development’. The reporting period is limited to the year ending December 2025. See the user guide for more details

In YE December 2025, 8,234 FNOs left immigration detention.

Just over a third (36%) of people leaving detention in the YE December 2025 were FNOs. The most common nationalities among these FNOs were Albanian (2,144), Romanian (1,057) and Polish nationals (673).

The most common offence groups among FNOs leaving in YE December 2025 were drug offences (3,081), theft offences (1,070) and violence against the person outside of homicide (1,042).

Although sentence length varied across offence groups, the most common sentence length group was between 2 to 4 years (2,218). Of all the FNOs leaving immigration detention in YE December 2025, 7% had been sentenced to prison terms of 8 years or over, and 32% had been sentenced to terms of under one year.

FNOs leaving detention to be returned from the UK will appear in the FNO returns statistics reported in the ‘How many people are returned from the UK?’ chapter. Those for whom there is no immediate prospect of their removal from the UK, or while an additional claim is being considered which creates a barrier to their return (for example, asylum claim) may leave detention on immigration bail and be managed in the community. These individuals are among those reported in the ‘FNOs in the Community’ statistics, published in the quarterly ‘Immigration Enforcement transparency statistics’.

4. About the statistics

The statistics in this section relate to detention under immigration powers.

One individual may enter or leave detention multiple times in a given period and will therefore have been counted multiple times in the statistics.

As set out in the Home Office’s intention to publish statement in April 2025, additional statistics on FNOs leaving immigration detention including breakdowns by most common nationality, offence group and sentence length group have been published in the immigration detention summary tables accompanying this release, following improvements to FNO data collection and infrastructure that have enhanced data quality.

These statistics are labelled as “Official statistics in development”. They are based on information from Home Office administrative systems, some of which are derived from case workers interpreting information held on Police National Computer records. We are developing how we collect the data and produce the statistics to improve their quality. See the user guide for more details.

5. Data tables

Data referred to here can be found in the following tables:

• Immigration detention summary tables
• Detailed immigration detention datasets

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See Section 6 of the ‘About this release’ section for more details.