This briefing examines immigration detention in the UK. It discusses the number of people detained, their characteristics, and how long they are detained for. It also examines the detention of women and children, the financial costs of operating the system, and compensation payments made for unlawful detention.
- COVID-19 substantially reduced the use of immigration detention in the UK, which has since largely rebounded to pre-pandemic levels.
- In 2021, around 24,500 people entered immigration detention in the UK – a return to pre-pandemic levels.
- From 2009 to 2019, the immigration detention population ranged from around 1,600 to 3,500 people, before falling to a record low in 2020 due to pandemic-related releases and returning to pre-pandemic levels.
- In 2021, the Home Office detained 100 children for immigration-related purposes, down from around 1,100 in 2009.
- Of the 24,500 who entered immigration detention in 2021, 78% were the citizens of ten countries.
- In 2021, 13% of immigration detainees were held for more than 28 days.
- In 2021, 86% of people leaving immigration detention were released on bail – higher than usual, due in part to the Home Office detaining people arriving in Dover for short periods before releasing them due to an asylum claim.
- In 2021, 81% of those entering immigration detention had previously claimed asylum in the UK – up from 66% in 2020.
- The Home Office estimates that since 2002 at least 112 members of the Windrush generation may have been unlawfully detained.
- In Q1 2022, the average cost to hold one person in immigration detention was around £107 per day, the highest since records began in 2013.
- In the financial year 2021-22, the Home Office issued a record number of compensation payments for unlawful detention, totalling around £13 million.
- COVID-19 substantially reduced the use of immigration detention in the UK, which has since largely rebounded to pre-pandemic levels.
Understanding the Policy
Immigration detention refers to the Home Office practice of detaining foreign nationals for the purposes of resolving their immigration statuses. Immigration detention is an administrative process, rather than a criminal justice procedure, meaning that the decision to detain is typically made by Home Office civil servants rather than courts, although it can result from a court decision regarding deportation. ... Click to read more.
Policy reasons for detaining typically include one or more of the following: to remove the person from the UK; to establish their identity or the basis of their immigration or asylum claim; where there is reason to believe they will abscond if released on bail; or when release is not considered to be ‘conducive to the public good’. In some instances, the reasons for a person’s detention change while they are being held. Detention typically ends in either removal from the UK, or release, usually on immigration bail.
The Home Office has the administrative power to detain a non-citizen at any point in their immigration process. This includes: upon arrival in the UK; upon presentation to an immigration office within the country; during a check-in with immigration officials; once a decision to remove has been issued; following arrest by a police officer; or sometimes after completing a prison sentence.
The Home Office detains people in Immigration Removal Centres (IRCs), Residential Short-Term Holding Facilities (RSTHFs), a pre-departure accommodation facility (PDA), short-term holding rooms based at ports of entry (also known as short-term holding facilities, or STHFs), and prisons, usually where a person has completed a prison sentence.
On 31 March 2022, 56% (807) of those in immigration detention were held in IRCs, 0.8% (12) in RSTHFs, and nobody was held in pre-departure accommodation. The Home Office does not publish statistical records of who it detains in short-term holding rooms. It is notable that 43% (621) were held in prisons under immigration powers, up from 10% (330 out of 3,455) on 30 September 2017, when the Home Office officially began publishing statistics on the number of people detained in prisons.
Detention is legally a last resort. Home Office policy and international law state that “Detention must be used sparingly, and for the shortest period necessary” (UK Visas and Immigration, 2016, para. 55.1.3). As of 15 January 2018, Schedule 10 to the Immigration Act 2016, on Immigration Bail, introduced automatic bail hearings after four months of detention that are presided over by an independent ‘First-tier Tribunal’ adjudicator. Home Office senior officials must now authorise detention continuance after a bail hearing. Unlike other European countries, the UK does not legislate upper time limits for individual detention periods.
The UK detention system’s facilities
As of 30 June 2022, the UK detention system comprised the following facilities (Home Office, 2022a):
- seven immigration removal centres:
- Brook House – male only; at Gatwick Airport
- Colnbrook – male and female (short term); at Heathrow airport
- Derwentside – female only; in County Durham
- Dungavel – male and female; in South Lanarkshire, Scotland
- Harmondsworth – male only; at Heathrow Airport
- Tinsley House – male and female; families with or without children; at Gatwick airport
- Yarl’s Wood – male and female; families without children; in Bedfordshire
- two residential short-term holding facilities to hold people for up to a week:
- Manchester STHF (formerly Pennine House) – at Manchester Airport
- Larne House STHF – in County Antrim, Northern Ireland
- one pre-departure accommodation (PDA) facility at Gatwick Airport within Tinsley House, which was closed due to the pandemic from 27th March 2020 for the rest of the year, and is for the short-term detention of families
- units for the short-term detention of people for up to one week located within Harmondsworth IRC, Tinsley House IRC, Yarl’s Wood IRC, and the Sahara Unit for women, which is in Colnbrook IRC
- several holding rooms, also known as non-residential short-term holding facilities (STHFs), run by Border Force in ports, airports, and at reporting centres across the country, where detainees may be held for up to 24 hours
- prisons, in which the UK also detains people post-sentence for immigration purposes.
As part of the ‘juxtaposed controls’ system established by the Sangatte and Touquet treaties, the UK Border Force subcontracts operational responsibility for four STHFs in Northern France. Two STHFs are in Coquelles near the Eurotunnel; and one is located within each of the ports of Calais and Dunkerque (Dunkirk). As of November 2019, the private contractor Mitie Care and Custody holds the contract to manage the three STHFs at Coquelles and Calais, while Eamus Cork Solutions manages the fourth STHF in Dunkerque (HM Chief Inspector of Prisons, 2020).
There are 13 reporting centres in the UK, where some detainees are first detained and where many must subsequently report routinely as a bail condition for their release. In March 2020, the Home Office announced the temporary suspension of reporting as a condition of immigration bail due to the COVID-19 pandemic. Reporting has now resumed.
The Home Office has outsourced its IRCs’ management to private, for-profit prison firms. Until recently, this included the GEO Group, which managed Dungavel; and G4S, which managed Brook House and Tinsley House. From late September 2021, Mitie and Serco have been managing all of the UK’s IRCs. Mitie runs the Heathrow IRCs (Colnbrook and Harmondsworth), took over Dungavel from GEO in 2021, and holds the contract for a new IRC, Derwentside, in County Durham. Serco manages Yarl’s Wood as well as Brook House and Tinsley House at Gatwick Airport. In 2011, the contract for managing the holding rooms, and two of the three STHFs, passed to Reliance (now Tascor).
The Home Office has closed several IRCs in recent years as part of a planned reduction of the UK’s detention system. IRCs Dover and Haslar closed in 2015. The Verne closed in December 2017 and returned to its previous purpose as a men’s prison. Campsfield House closed in December 2018. Morton Hall has returned to prison use, though with an RSTHF on site for men and women.
Between 2011 and 2016, the Cedars Pre-Departure Accommodation operated in West Sussex, where the charity Barnardo’s oversaw welfare services delivered to families detained for short periods before removal. A “discrete self-contained unit” at Tinsley House IRC opened to accommodate families in May 2017. Families may be held for up to 72 hours, with a ministerial declaration for “exceptional” cases extending a family’s stay to no more than seven days.
Women in immigration detention
The detention of women, and especially pregnant women, has attracted sustained criticism. Most notably, Yarl’s Wood, which until August 2020 was the primary IRC for women, was described in a 2015 report by Her Majesty’s Inspector of Prisons as a “place of national concern”, though a 2017 inspection reported “significant improvements”.
Home Office policy states that pregnant women may be detained only if removal is imminent or there are exceptional circumstances to justify detention. In 2016, a 72-hour time limit on the detention of pregnant women was enacted, although a government minister can extend this to a maximum of seven days.
A new IRC called Derwentside opened in County Durham on 23 November 2021 (Home Office, 2022a). Previously known as Medomsley or the Hassockfield Secure Training Centre for young offenders, Derwentside is the only IRC solely for women, with a capacity of 84 beds (Legal Aid Agency, 2021, p. 8). Small numbers of women can also be detained at Colnbrook (called Colnbrook STHF in Home Office statistics) and Dungavel; in residential STHFs like Manchester and Larne House; and in the Kent Intake Unit at Dover.
Housing asylum seekers in Penally Camp and Napier Barracks
During the COVID-19 pandemic, and in response to an increase in migrants arriving from France in small boats, the Home Office has been holding asylum seekers have been held in “contingency” accommodation (see our Q&A: Migrants crossing the English Channel in small boats). From 21 September 2020, this included two military sites: Penally Training Camp in Wales (which held around 200 people at its peak (Neal, 2021a, p. 33); and Napier Barracks in Folkestone (which held around 400 asylum seekers at its peak in January 2021 (Neal, 2021a, p. 12)). Penally Camp closed on 21 March 2021. On 3 June 2021, the High Court ruled that accommodating asylum seekers at Napier Barracks was unlawful: conditions did not meet minimum legal standards for asylum accommodation; and detaining people during a COVID-19 outbreak violated Article 5 of the European Convention on Human Rights. The judge described the conditions as “detention-like” (p. 39). The Guardian reported that as at 22 June 2021, around 230 asylum seekers continued to be housed in Napier, though the Home Office had suspended transfers there.
Understanding the Evidence
The publicly available data on immigration detention are found primarily in publications of the Home Office and Her Majesty’s Inspectorate of Prisons (HMIP). Home Office detention statistics record people detained under Immigration Act powers, and not foreign nationals serving criminal sentences. The statistics exclude people detained for less than 24 hours in short-term holding rooms at seaports, airports and in police cells. ... Click to read more.
Data on those entering detention are counts of the number of occurrences of people entering detention rather than the number of unique individuals. Thus, an individual who enters detention, say, twice in a given period, would be counted twice in the data. Nevertheless, in this briefing we use the term “people entering detention” for ease of expression.
Data on those detained in prison are included from Q3 2017 onwards, but do not include people detained in police cells and short-term holding rooms at ports and airports (for less than 24 hours), nor those detained under both criminal and immigration powers and their dependants. As such, counts from Q3 2017 onwards are not comparable with those for earlier periods.
Data on those in detention relate to those in detention on the last day of the quarter, where Q1 = 31 March, Q2 = 30 June, Q3 = 30 September, and Q4 = 31 December.
COVID-19 substantially reduced the use of immigration detention in the UK, which has since largely rebounded to pre-pandemic levels
COVID-19 significantly reduced immigration detention in the UK (Figure 1). During 2020, both the number of people entering detention and the detainee population fell substantially, especially during Q2 2020, though numbers have since returned to levels comparable with those seen pre-pandemic. The number of people removed from the UK from detention also declined, and has not returned to pre-pandemic levels.
The Home Office suggests that the large increase in the number of people being released on immigration bail reflects the large number of irregular boat arrivals, who are detained for short periods for the purpose of migration management before being released due to an asylum claim (see below on immigration bail).
In 2021, around 24,500 people entered immigration detention in the UK – a return to pre-pandemic levels
From 2009 to 2021, the number of people entering detention each year has ranged from around 15,000 to 32,000 (Figure 2). The number increased each year from 2010, reaching a peak of 32,447 in 2015.
In 2020, around 15,000 people entered detention, 40% lower than in 2019 before the pandemic, and around 55% lower than its peak in 2015. This number was by far the lowest since 2009 when the current official data series begins, and due largely to the pandemic. The number rebounded to pre-pandemic levels in 2021.
In any given year, a large majority of those entering detention are male – between 81% and 94% – with 2021 recording the smallest share of women or girls entering detention in the 12 years from 2010 to 2021, at 2%. This was in part due to the increasing detention of people who had arrived by small boat – 83% of whom were men in 2021 (Home Office, 2022b).
From 2009 to 2019, the immigration detention population ranged from around 1,600 to 3,500 people, before falling to a record low in 2020 due to pandemic-related releases and returning to pre-pandemic levels in 2021
In February 2021, the capacity of the UK’s detention facilities was 2,513 (Neal, 2021b, p. 24). This included Morton Hall (capacity: 352), which has since closed, and not Derwentside, which opened in November 2021 and is reported to have a capacity of 84 (Women for Refugee Women, 2022). Accordingly, the estimated capacity stands at 2,245 for the UK’s immigration detention facilities as of 2022.
From 2009 to 2019, the Home Office detained a minimum of around 1,600 people, to a maximum of around 3,500 (Figure 3).
On 30 June 2022, there were 2,038 people detained under Immigration Act powers, including 544 people detained in prisons. This is around three times the size of the total detained population at the end of June 2020 (698, with 368 in prisons) at the height of the pandemic, and comparable to pre-pandemic levels at the end of September 2019 (1,826).
In recent years, the Home Office has been holding more people (in absolute terms) under Immigration Act powers in prisons. The Home Office has said that this is due to “difficulties in securing returns due to the global travel restrictions caused by the pandemic, as well as challenges around releasing some foreign national offenders (FNOs) into the community” (Home Office, 2022c).
The post-2015 population decline is likely to have resulted from several factors. First is the end of the Detained Fast Track policy, which ran from 2000 until July 2015 and enabled mandatory detention for non-citizens whom the Home Office considered to be candidates for a quick resolution to their immigration statuses. Second, is the government’s commitment, following the Shaw reviews into welfare in detention of vulnerable people (Shaw, 2016; Shaw, 2018), to reduce immigration detention (gov.uk, 2018). In response to the first Shaw review, the government introduced a policy, ‘Adults at risk in immigration detention’, which aimed to strengthen the presumption against detaining people (Home Office, 2021). The Home Office also closed the following IRCs: Dover and Haslar in 2015, which provided a combined total of approximately 600 places, The Verne in 2017 (600 places), Campsfield House in 2019 (around 300 places), and Morton Hall in 2021 (400 places) (for capacity of facilities: Bolt, 2020).
Home Office analysis has suggested that falls in the detained population in 2018 might have resulted from (1) the commencement on 15 January 2018 of Schedule 10 to the Immigration Act 2016, on Immigration Bail, which introduced automatic bail hearings for most detainees four months after entering detention; and (2) changes to the immigration system spurred by the “Windrush scandal” (Home Office, 2019a) that included colleagues checking caseworkers’ decisions, and increasing face-to-face contact time between caseworkers and detainees (Joint Select Committee on Human Rights, 2019).
In 2021, the Home Office detained 100 children for immigration-related purposes, down from around 1,100 in 2009
In recent years, few people under 18 or people who are 50 or older, have entered detention. In 2021, 97% of people entering immigration detention were between 18 and 49 years old (see Figure 4).
Throughout the 1990s, the Home Office rarely detained families with children. But between 2005 and 2009, non-governmental organisations and other groups estimated that the number of children detained with their families was up to 2,000 per year (Crawley and Lester, 2005; Sankey et al., 2010).
Home Office statistics record that in 2009, 1,119 children entered detention. After a policy change under the Conservative and Liberal Democrat coalition government, and the opening of Cedars Pre-Departure Accommodation, the number of detained children fell substantially, standing at 100 in 2021 (Figure 4).
Of the 24,500 who entered immigration detention in 2021, 78% were the citizens of ten countries
Of the roughly 24,500 people who entered immigration detention in 2020, 78% were citizens of ten countries (Table 1). In part, these patterns reflect the total number of people of each nationality in the UK. They also reflect the recent trend of the short-term detention of people who arrived in the UK via small boat.
The number of EU citizens entering immigration detention increased significantly in recent years, from 768 in 2009, to a peak of 5,319 in 2017. The numbers fell in subsequent years, and in 2021, EU citizens made up 10% of all those entering detention (Figure 5). The majority of EU citizens detained in the UK are from Eastern Europe, including Romania and Poland.
In 2021, 13% of immigration detainees were held for more than 28 days
Unlike most European countries, the UK has not legislated a statutory upper time limit on individual periods of immigration detention. Of all people leaving detention in 2021, 87% had been detained for less than 29 days, 6% for 29 days to under 2 months, 6% for 2 months to under 6 months, 1% for 6 months to under 1 year, and 0.4% had been detained for 1 year or longer (Figure 6).
In recent years, the proportion of people detained for shorter has increased. The Home Office attributes this change to an increasing proportion of detainees – many of whom arrived by small boat – being detained for short periods after arrival in Dover before being released on bail (see Figure 7), most commonly due to an asylum application being made (Home Office, 2022c).
Female detainees are on average held for shorter periods than male detainees (Figure 6).
On 31 March 2022, the longest-serving detainee had been held for 1,391 days – almost three years and ten months (Home Office, 2022d).
Campaign groups and health professionals have argued that the uncertainty concerning how long a person will be detained is harmful to detainees and their family and friends. A range of stakeholders have argued for legislating a maximum limit on individual periods of detention, including: HM Chief Inspector of Prisons (2020); the All Party Parliamentary Group on Refugees and the All Party Parliamentary Group on Migration (2015); and the House of Commons Home Affairs Committee (2019).
In 2021, 86% of people leaving immigration detention were released on bail – higher than usual, due in part to the Home Office detaining people arriving in Dover for short periods before releasing them due to an asylum claim
Over the last decade, there has been a long-term fall in the share of people leaving immigration detention to be returned to their country of nationality or habitual residence. In 2010, 64% of people leaving detention left the UK directly, either voluntarily or under Home Office enforcement. In 2021, this had fallen to 13% (Figure 7). By contrast, those released into the community on immigration bail reached a record high in 2021: 86%. The Home Office suggests that the spike in bail releases in 2021 does not reflect an increase in detainees having applied successfully for release on bail in the usual way. Rather, it is because the Home Office is increasingly detaining people arriving in Dover for short periods before releasing them on bail, most commonly due to an asylum claim.
In 2021, 81% of those entering immigration detention had previously claimed asylum in the UK – up from 66% in 2020
There are several categories of people detained under Immigration Act powers. Some individuals fall into more than one category. These categories include: new arrivals awaiting examination by an immigration officer to determine their right to enter the UK; new arrivals who have been refused permission to enter the UK and are awaiting removal; those who have either failed to leave the UK on expiry of their visas (visa overstayers), or who have not complied with the terms of their visas, or have attained their visas by deception; and people in the UK who are awaiting a decision on whether they are to be removed, or who are awaiting their removal, such as refused asylum seekers.
The largest category of immigration detainees comprises people who have sought asylum at some stage during their immigration process, including while in detention. In 2021, detainees who had previously sought asylum accounted for 81% (19,886) of people entering detention – the highest since records began in 2010 (Figure 8). The notable increases from 2019 to 2021 inclusive have coincided with increases in people arriving by small boat, many of whom the Home Office reports it detains for short periods for the purposes of migration management before releasing them on bail due to an asylum claim being raised.
The Home Office estimates that since 2002 at least 112 members of the Windrush generation may have been unlawfully detained since 2002
The Home Office has in some cases detained long-term legal residents or even British citizens who are unable to prove their status, as illustrated by the 2018 Windrush situation (see Williams, 2020). The Home Office Windrush Historical Cases Review examined the immigration records of 11,800 British residents of Caribbean Commonwealth nationality who were born before 1973 and who had been held in immigration detention or removed from the UK since 2002. The review found that 112 such members of the Windrush generation had been detained, of whom 31 were removed (Home Office, 2019b; see also Williams, 2020). The government has not confirmed whether these individuals were all unlawfully detained, because it has not been able to trace nine of them.
In Q1 2022, the average cost to hold one person in immigration detention was around £107 per day, the highest since records began in 2013
The annual financial cost of operating the UK’s detention system for the year ending March 2022 was around £94 million, down from around £144 million in the year ending March 2014 (Figure 9, left chart). The lower costs accrue from reductions in the size of the detention system, and fewer people being held in immigration detention.
The average daily cost of keeping an individual in immigration detention has increased gradually from a low of £85 in Q1 2017 to a high of £107 in Q1 2022 (Figure 9, right chart).
In the financial year 2021-22, the Home Office issued a record number of compensation payments for unlawful detention, totalling around £13 million
Courts may order the Home Office to compensate people who have been detained unlawfully. In recent years, the Home Office has issued an increasing number of compensation payments for unlawful detention. In the year ending March 2022, there were 572 proven cases of unlawful detention, for which a total of £12.7 million was paid in compensation – up from £0.8m for 38 cases in 2014-15 (Figure 10).
Evidence Gaps and Limitations
There are two notable deficiencies in the available data on immigration detention in the UK. First, it is not possible to track individual trajectories of detention, release, and re-detention through the statistics, because the Home Office presents data for separate numbers of occurrences of entering detention, rather than data for unique individuals. Second, the Home Office does not provide information in the public statistics about how many people are being held on which policy ground for detention, and whether they have been released from detention or removed from the UK.
With thanks to Ali McGinley, and Gemma Lousley at Women for Refugee Women, and officials at the Home Office for extremely helpful comments on drafts of this briefing. We are also grateful to CJ McKinney, and Bella Sankey of Detention Action, for thorough and detailed comments on the 2020 update of this briefing. Mary Bosworth provided detailed feedback on early drafts of this briefing, and on the 2022 version, for which we are most thankful. Final thanks go to Frances Timberlake of Refugee Rights Europe, for information on short-term holding facilities in Northern France; and Kotaro Oriishi for valuable assistance updating the figures and data for the 2022 version of this briefing.
- All Party Parliamentary Group on Refugees & All Party Parliamentary Group on Migration (2015). The report of the inquiry into the use of immigration detention in the United Kingdom. London, UK: APPG.
- Bolt (2020). Annual inspection of ‘Adults at Risk in Immigration Detention’ (2018–19). London, UK: Independent Chief Inspector of Borders and Immigration.
- Crawley, H. (2011). Detention by another name? London, UK: Migrants’ Rights Network.
- HM Chief Inspector of Prisons, accompanied by the Contrôleur Général des Lieux de Privation de Liberté (2020). Report on unannounced inspections of the UK short-term holding facilities at France-UK Borders, 25–27 November 2019. London, UK: Her Majesty’s Inspectorate of Prisons.
- uk (2018). Government response to Stephen Shaw’s review into the welfare in detention of vulnerable persons.
- Home Office (2019a). Immigration statistics quarterly release, How many people are detained or returned? London, UK: Home Office.
- Home Office (2019b). Windrush Update from Home Secretary to the Home Affairs Select Committee: Letter from Home Secretary Priti Patel to Rt Hon Yvette Cooper MP, Chair of the Home Affairs Select Committee (HASC). London, UK: Home Office.
- Home Office (2021). Adults at risk in immigration detention. London, UK: Home Office.
- Home Office (2022a). User guide to Home Office immigration statistics. London, UK: Home Office.
- Home Office (2022b). Irregular migration to the UK, year ending March 2022. London, UK: Home Office.
- Home Office (2022c). Immigration statistics, year ending March 2022: How many people are detained or returned? London, UK: Home Office.
- Home Office (2022d). Immigration statistics quarterly release, 27 May 2022, Detention summary tables, year ending March 2021, Table Det_03d. London, UK: Home Office.
- House of Commons Home Affairs Committee (2019). Immigration detention: Fourteenth report of session 2017–19. London, UK: House of Commons.
- Joint Select Committee on Human Rights (2019). Windrush generation detention: Government Response to the Committee’s Sixth Report of Session 2017–19. London, UK: House of Commons.
- Legal Aid Agency (2021). Procurement of Detained Duty Advice Scheme Services at Derwentside Immigration Removal Centre from 1 January 2022 Invitation To Tender Information for Applicants.
- Neal, D. (2021a). An inspection of contingency asylum accommodation: HMIP report on Penally Camp and Napier Barracks. London, UK: Independent Chief Inspector of Borders and Immigration.
- Neal, D. (2021b). Second annual inspection of ‘Adults at risk in immigration detention’. London, UK: Independent Chief Inspector of Borders and Immigration.
- Sankey, I., Farthing, S., & Coles, A. (2010). Liberty’s submission to the review into ending the detention of children for immigration purposes. London, UK: Liberty.
- Shaw, S. (2016). Review into the welfare in detention of vulnerable persons: A report to the Home Office by Stephen Shaw. London, UK: HMSO.
- Shaw, S. (2018). Assessment of government progress in implementing the report on the welfare in detention of vulnerable persons: A follow-up report to the Home Office by Stephen Shaw
- UK Visas and Immigration (2016). Enforcement instructions and guidance, Chapter 55: Use of detention. London, UK: Home Office.
- Women for Refugee Women (2022). Women for refugee women mounts a legal challenge against the Home Office.
- Williams, W. (2020). Windrush lessons learned review. London, UK: Her Majesty’s Stationery Office.
Independent (26 Oct 2016)
- Independent (26 Oct 2016)