National statistics

How many people are detained or returned?

Updated 3 March 2022

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Data on immigration detention relates to 2021 and all comparisons are with 2020, unless indicated otherwise.

Data on returns relate to the year ending September 2021, to allow more time for returns to be recorded on the system and ensure the published figures are an accurate representation of the number of returns. Comparisons are with the year ending September 2020, unless indicated otherwise.

See the user guide for more details.

On 11 March 2020, the World Health Organisation (WHO) declared the COVID-19 outbreak as a global pandemic. A range of restrictions were implemented in many parts of the world, and the first UK lockdown measures were announced on 23 March 2020. The COVID-19 pandemic has had a significant impact on the UK immigration system, both in terms of restricting migrant movements to and from the UK and the impact on operational capacity. Year ending comparisons that follow will include impacts resulting from the restrictions put in place during this period of the pandemic.

This section contains data on:

• Individuals detained under Immigration Act powers
• Returns of people who do not have any legal right to stay in the UK

1. Immigration detention

24,497 people entered immigration detention in 2021, 65% higher than the previous year when there was a large fall following the COVID-19 outbreak. The number of people entering detention is now similar to pre-pandemic levels but the profile of detainees and their length of detention is different. Since the pandemic, an increasing proportion of those entering detention have been recent clandestine arrivals detained for short periods in order to confirm their identity and provide initial support on arrival.

There has been a general downward trend in the number of people entering detention since the peak in 2015, as shown in Figure 1, when over 32,000 people entered detention.

Iranians were the most common nationality entering detention in the latest year, accounting for 19% of the total, or 4,667 entrants, two and a half times more than last year. Albanians were the next most common with 3,708 entrants, just over double the number last year. Most other nationalities in the top 10 saw an increase in numbers entering detention, reflecting the general return to levels prior to the pandemic.

Figure 1: People entering immigration detention in the UK, 2010 to 2021

Source: Immigration detention - Det_D01

At the end of December 2021, there were 1,179 people in immigration detention (including those detained under immigration powers in prison), 69% more than at the end of June 2020 (698) when the impact of the pandemic was most pronounced, but 28% fewer than pre-pandemic levels at the end of December 2019 (1,637).

Figure 2 shows the number of people detained in prisons under immigration powers increased by 85% from 359 before the pandemic at the end of December 2019 to 665 at the end of December 2021. This may reflect falls in the number of returns, as well as challenges around releasing some foreign national offenders (FNOs) into the community. The number detained in the detention estate (IRC, STHF & PDA) fell immediately following the pandemic and has remained below pre-pandemic levels since (541 at the end of December 2021 compared with 1,278 at end of December 2019, before the pandemic).

The number of people in detention relate to a specific point in time and are subject to daily fluctuations. For example, if there were a large number of clandestine arrivals who had to be brought into detention just before the end of the period, the number of people in detention may be higher than if the same arrivals occurred several weeks before the end of the period.

Figure 2: People detained under immigration powers in the UK, by place of detention, as at the last day of the quarter, 2018 Q1 to 2021 Q4^1,2

Source: Immigration detention - Det_D02
Notes:

1. The ‘detention estate’ comprises Immigration Removal Centers (IRC), Short Term Holding Facilities (STHF) and Pre-departure Accommodation (PDA). It excludes those who are detained under Immigration powers in prisons.
2. 2019 Q4 is the last data point before the pandemic with 2020 Q1 being immediately following the first UK lockdown.

Figure 3 shows that an increasing proportion of people who were detained spent short periods in detention with 76% of those who left detention in 2021 detained for seven days or less. This is a higher proportion than the 54% in 2020 and the 39% pre-pandemic in 2019. The change is in part due to an increasing proportion of detainees being detained for short periods on arrival to the UK before being bailed (86% of those leaving detention in 2021 were bailed) with the most common reason being an asylum (or other) application being raised. This combined with falling returns has led to a fall in the proportion of detainees being returned from detention; 13% (3,086) in 2021, down from 37% (9,081) pre-pandemic in 2019 and 64% (16,577) in 2010.

Figure 3: People leaving immigration detention, by length of detention^1,2, 2017 to 2021

Source: Immigration detention - Det_D03
Notes:

1. Data from July 2017 includes those leaving detention through HM Prisons. Data are not directly comparable with previous years. See the user guide for more details.
2. ’ < ‘ means ‘less than’.

Figure 4 shows that among the top 10 nationalities leaving detention in 2021 the majority were bailed. Only Albanian, Romanian and Polish nationals saw notable numbers of returns.

Figure 4: Top 10 nationalities leaving detention by reason for leaving^1,2, 2021

Source: Immigration detention - Det_D03

Notes: 1. Bailed (SOS & IJ) Secretary of State & Immigration Judge. 2. Other reasons for leaving detention include being sectioned under the Mental Health Act, entering criminal detention, being granted leave to enter or remain in the UK, and detained in error. See the user guide for more details.

2. Returns

In the year ending September 2021, enforced returns from the UK decreased to 2,830, around a third (35%) fewer than the previous year and 61% fewer than pre-pandemic levels in 2019. The vast majority of enforced returns in the latest year were of Foreign National Offenders (FNOs).

Enforced returns have been declining since the peak in 2012, as Figure 5 shows, with the recent sharp fall related to the impact of the COVID-19 pandemic. The number of enforced returns were very low during quarters that coincided with lockdowns starting in late March 2020 and early January 2021 (362 and 422). Numbers have increased to around 800 per quarter, however this is still below pre-pandemic levels (which saw around 1,800 returns per quarter).

In the year ending September 2021, there were 5,537 voluntary returns, 17% fewer than last year and 56% lower than pre-pandemic in 2019. This reduction continues a downward trend since the peak in 2015.

There were 16,456 passengers who were refused entry at port and subsequently departed (‘port returns’) in the year ending September 2021, which represents an increase of 40% compared with the previous year. The number of port returns in 2020 Q2 fell significantly as very few passengers arrived in the UK immediately following the outbreak of the COVID-19 pandemic. The number of port returns has since increased as more passengers began to arrive to the UK and in the most recent quarter were above pre-pandemic levels.

Port returns of EU nationals have increased from the start of 2021, with 9,353 returns in the first 9 months of the year, following the departure of the UK from the EU. Port returns of non-EU nationals display a much less marked increase than EU nationals since the start of 2021, and are around two thirds (67%) lower than the first 9 months of 2019.

Figure 5: Returns from the UK, by type of return¹, year ending September 2011 to year ending September 2021

Source: Returns - Ret_D01

Notes:

1. ‘Voluntary returns’ include ‘other verified returns’ which are subject to upward revision (particularly for the last 12 months) as in some cases it can take time to identify people who have left the UK without informing the Home Office.

The longer-term fall in returns is due to a number of factors. The majority of enforced returns occur from detention. As reported in ‘issues raised by people facing return in immigration detention’, (Home Office, 2021), nearly three-quarters of people detained within the UK following immigration offences in 2019, were recorded as having raised one or more ‘issues’ that may have prevented their return. These could be an asylum claim, legal challenge, or claiming to be a potential victim of modern slavery or human trafficking. This was up from 63% of detainees in 2017.

As Figure 6 shows, prior to the pandemic, the number of enforced returns of non-EU nationals had fallen from 13,647 in the year ending September 2012 to 3,719 in 2019. Enforced returns of EU nationals also decreased in recent years from 5,023 in the year ending June 2017 to 3,479 in 2019. Returns of both EU and non-EU nationals continued to fall following the COVID-19 pandemic.

Figure 6: Enforced returns from the UK, for EU and non-EU nationals, year ending September 2011 to year ending September 2021

Source: Returns - Ret_D01

The top 4 nationalities accounted for two thirds of enforced returns in the year ending September 2021 - these were nationals of Romania (23%), Albania (22%), Poland (11%), and Lithuania (9%). Three of the top 4 (except Albania, which saw similar levels) and most other nationalities saw decreases in enforced returns in the year ending September 2021, compared with the previous year.

2.1 Returns of foreign national offenders (FNOs)

In the year ending September 2021, there were 2,732 FNOs returned from the UK, 20% fewer than the previous year and 47% fewer than in 2019 before the pandemic began. As Figure 7 shows, FNO returns had fallen to 5,128 in 2019, following a steady increase between 2011 and 2016, due to more FNOs from the EU being returned in that period.

FNO figures are a subset of the total returns figures and currently constitute 33% of enforced and voluntary returns, with the majority being enforced returns.

Of the 2,732 FNOs returned from the UK in the year ending September 2021:

• 62% were EU nationals (1,705)

• 38% were non-EU nationals (1,027)

Figure 7: Returns of FNOs¹ from the UK, for EU and non-EU nationals, year ending September 2011 to year ending September 2021

Source: Returns - Ret_D03

Notes: 1. An FNO is someone who is not a British citizen and is, or was, convicted in the UK of any criminal offence, or convicted abroad for a serious criminal offence.

2.2 Asylum related returns

In the year ending September 2021, there were 976 returns of people who had previously claimed asylum in the UK (see section 3.2 below for the definition of an asylum-related return), around half the number in the previous year (1,989) and 71% fewer than prior to the pandemic in (3,332 returns). This continues a downward trend since 2010, when there were 10,663 asylum-related returns. This sharp fall over the decade differs from non-asylum related returns, which were relatively stable until 2016 and have only been falling since.

3. About the statistics

3.1 Immigration detention

The statistics in this section show the number of entries into, and departures from, detention for those held solely 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. Statistics on foreign nationals held in prison for criminal offences are published by the Ministry of Justice in ‘Offender management statistics quarterly’.

The detention estate comprises immigration removal centres (IRC), short-term holding facilities (STHF) and pre-departure accommodation (PDA).

Data on those entering detention, by place of detention, relate to the place of initial detention. An individual who moves from one part of the detention estate to another will not have been counted as entering any subsequent place of detention. The data, therefore, do not show the total number of people who entered each part of the detention estate.

Data on those in detention relate to those in detention on the last day of the quarter. It is therefore subject to daily fluctuations and can depend on how many people entered detention just before the end of the period.

Data on those leaving detention, by place of detention, relate to the place of detention immediately prior to being released. An individual who moves from one part of the detention estate to another has not been counted as leaving each part of the detention estate. The data, therefore, do not show the total number of people who left each part of the detention estate.

From July 2017, data on detention of immigration detainees in prisons are included in the immigration detention figures. Previously, individuals who were detained in prison would have been recorded in the data upon entering the detention estate through an IRC, STHF or PDA; now they are recorded upon entering immigration detention within prison. As a result, the length of detention of those entering prison prior to July 2017 will be recorded from the point at which they entered an IRC, STHF or PDA. Time spent in prison under immigration powers prior to entering an IRC, STHF or PDA is not included in the length of detention figures prior to July 2017.

For those entering detention from July 2017, the length of detention will include time spent in prison under immigration powers prior to entering an IRC, STHF or PDA. Data from 2017 Q3 onwards are therefore not directly comparable with earlier data. Further details of these changes can be found in the user guide.

Following the introduction of the new Immigration Bail in Schedule 10 of the Immigration Bill 2016, the reason for leaving detention ‘Bailed (SoS)’ replaced the existing powers of ‘granted temporary admission/release’ from 15 January 2018, and ‘Bailed (Immigration Judge)’ replaced Bailed’ to differentiate from ‘Bailed (SoS)’. See the user guide for more details of this change.

Data on the number of children entering detention is subject to change. This will be a result of further evidence of an individual’s age coming to light, such as an age assessment.

Data on deaths in detention include any death of an individual while detained under immigration powers in an IRC, STHF, PDA, under escort, or after leaving detention if the death was as a result of an incident occurring while detained or where there is some credible information that the death might have resulted from their period of detention and the Home Office has been informed. The annual data for 2020 are included in table Det_05b in the Detention summary tables. Further details can be found in the user guide.

3.2 Returns

Data on returns are published a quarter behind to allow more time for returns (particularly ‘other verified returns’) to be entered on the system prior to publication, ensuring that the published data is an accurate representation of the number of returns. We routinely revise the previous eight quarters of data as part of each quarterly release. Therefore, data for the most recent 8 quarters should be considered provisional. Further details on the revisions can be found in the returns section of the user guide.

The statistics in this section show the number of returns from the UK. One individual may have been returned more than once in a given period and, if that was the case, would be counted more than once in the statistics.

The Home Office seeks to return people who do not have a legal right to stay in the UK. This includes people who:

• enter, or attempt to enter, the UK illegally (including people entering clandestinely and by means of deception on entry)

• are subject to deportation action; for example, due to a serious criminal conviction

• overstay their period of legal right to remain in the UK

• breach their conditions of leave

• have been refused asylum

The term ‘deportations’ refers to a legally-defined subset of returns, which are enforced either following a criminal conviction, or when it is judged that a person’s removal from the UK is conducive to the public good. The published statistics refer to enforced returns which include deportations, as well as cases where a person has breached UK immigration laws, and those removed under other administrative and illegal entry powers that have declined to leave voluntarily. Figures on deportations, which are a subset of enforced returns, are not separately available.

Data on voluntary returns are subject to upward revision, so comparisons over time should be made with caution. In some cases, individuals who have been told to leave the UK will not notify the Home Office of their departure from the UK. In such cases, it can take some time for the Home Office to become aware of such a departure and update the system. As a result, data for more recent periods will initially undercount the total number of returns. ‘Other verified returns’ are particularly affected by this.

Asylum-related returns relate to cases where there has been an asylum claim at some stage prior to the return. This will include asylum seekers whose asylum claims have been refused and who have exhausted any rights of appeal, those returned under third-country provisions, as well as those granted asylum/protection but removed for other reasons (such as criminality).

Data on the number of people returned from the UK from detention in the ‘immigration detention’ tables includes those who were refused entry at port in the UK who were subsequently detained and then departed the UK. Data on those returned from detention in the ‘returns’ tables do not include those refused entry at port, and so figures will be lower.

Prior to the UK leaving the EU, certain individuals applying for international protection (asylum) could be returned from the UK to the relevant EU member state that was deemed responsible for examining the application, under the Dublin Regulation. Data on returns, and requests for transfer out of the UK under the Dublin Regulation, by article and country of transfer, are available from the Asylum data tables. Strengthened inadmissibility rules came into effect on 1 January 2021, following the UK’s departure from the EU. Data on cases dealt with under the inadmissibility rules, for January to September 2021, can be found in the How many people do we grant asylum or protection to? section. Further details on the Dublin Regulation and inadmissibility rules are set out in the user guide.

EU nationals may be returned for abusing or not exercising Treaty rights, or deported on public policy grounds (such as criminality).

Eurostat publishes a range of enforcement data from EU member states. These data can be used to make international comparisons.

3.3 Windrush Scheme

The Windrush generation refers to people from Caribbean countries who were invited by the British government between 1948 and 1971 to migrate to the UK as it faced a labour shortage due to the destruction caused by World War II. Not all of these migrants have documentation confirming their immigration status and, therefore, some may have been dealt with under immigration powers.

Data relating to the Windrush compensation scheme are published as part of the Home Office Transparency data.

4. Data tables

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

• Immigration detention summary tables

• Detailed immigration detention datasets

• Returns summary tables

• Detailed returns datasets

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