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Immigration by Category: Workers, Students, Family Members, Asylum Applicants

28 Jun 2018

This briefing examines the different routes or reasons for which migrants come to the UK. The analysis distinguishes between European and non-European migrants and among four basic types: work, study, family, and asylum.

  1. Key Points
    • Free movement from EU countries accounted for a growing share of long-term immigration until 2015
    • Work is the most common reason for migration to the UK and asylum is the smallest
    • Asylum applicants constituted 6% of all long-term migration to the UK in 2016
    • Administrative data sources and ONS estimates mostly agree on the share of migrants in each category, though administrative sources give higher raw figures than ONS estimates
  1. Understanding the Evidence

    The International Passenger Survey (IPS) is conducted by the Office for National Statistics (ONS), Long-Term International Migration (LTIM) estimates derived from IPS, while administrative data are from entry clearance visas issued. Asylum-related entries are handled by the Home Office and tracked in administrative data. Asylum applicants are also incorporated into LTIM, which includes other adjustments and is therefore preferable to pure IPS data when available.

    Crucially for this briefing, IPS/LTIM categorises migrants differently from administrative sources. IPS asks respondents to name their primary “reason for migrating”, and classifies migrants accordingly. Administrative data, by contrast, classify migrants by the type of visa they were granted or on which they entered the UK.

    IPS/LTIM also differs from visa data in terms of who is counted. IPS covers only migrants intending to change their usual place of residence for one year or more. Visa data also include short-term arrivals, who cannot always be distinguished from long-term migrants based on available data.

    IPS/LTIM data, unlike most administrative data, include migration of EU and British nationals. If work, study, family and asylum are considered “reasons for migration”, it makes little sense to consider EU migrants as a distinct category. If the four basic categories are thought of as different legal grounds for entry, however, then EU nationality (or more precisely EEA/Swiss nationality) can be sensibly considered a fifth category.

    This briefing focuses on arrivals (inflows) to Britain, and considers neither departures (outflows) nor net migration (balance) – the difference between arrivals and departures.

    The ONS has revised the total net migration figures for the United Kingdom in light of the 2011 Census estimates. The revision suggested that the total net migration between 2001 and 2011 was underestimated and missed a substantial number of A8 migrants from Eastern and Central Europe who arrived in the UK between 2004 and 2008, prior to the improvements of the IPS in 2009 (ONS, 2014). However, revised tables of inflows and outflows as well as breakdowns by citizenship or reason for migration are not currently available, so this briefing uses unrevised tables where necessary. Unrevised totals for 2011-2011 should not be compared directly with revised totals from 2012 onwards.

Free movement from EU countries accounted for a growing share of long-term immigration until 2015

The number of non-UK citizens moving to the UK for at least 12 months has fluctuated between 550,000 and 650,000 since 2004. While traditionally a significant majority of migration has been from outside of the EU, the share of EU citizens increased following EU enlargement in 2004. This was due to an increase in EU immigration and a decrease in non-EU immigration.

EU immigration slowed from 2009 to 2012 in the aftermath of the economic crisis, before rising again. By 2015, the estimated inflows of long-term immigrants from EU countries and non-EU countries were almost equal, at 49% and 51% of non-UK immigration respectively. EU immigration peaked in the year ending June 2016 (the year leading up to the EU referendum).

In 2016, an estimated 249,999 EU nationals moved to the UK for at least 12 months compared to an estimated 265,000 non-EU migrants. More recent provisional data for the year ending September 2017 suggest, however, that EU immigration has made up a smaller share of overall immigration since the referendum on EU membership in mid-2016.

Since 2002, immigration of British citizens has fluctuated between 70,000 and 100,000. In 2016, 74,000 British nationals moved to the UK for at least 12 months; this includes British citizens who have been away from the UK for at least a year, or British citizens born abroad coming here for the first time.

Note that Figure 1 presents only immigration, or “inflows”. For net migration by nationality, see the Migration Observatory briefing on ‘Who Counts as a Migrant? Definitions and their Consequences’.

Figure 1

Source: ONS, LTIM Estimates, 1991-2003: Table 2.01aa; 2004-2016: Table 2.01a

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Work is the most common reason for migration to the UK and asylum is the smallest

Work has been the most common reason given for migration to the UK since 2013, as shown in Figure 2. (“Work” combines two listed reasons for migrating: coming for “a definite job” and coming “to look for work”.) The work category decreased during the economic crisis, from 242,000 in 2007 to 184,000 in 2012 – the lowest total for the work category since 2003. In 2016, migration for work was 275,000, a decline from its 2015 level of 308,000.

Migration for formal study increased from 87,000 (18% of total arrivals) in 2001 and peaked at 238,000 in 2010. By 2016 it had declined to an estimated 137,000, following policy changes after 2011 that made it more difficult for educational institutions to sponsor non-EU students.

Family migration has fluctuated between 60,000 and 105,000 since 1991, but without a clear increasing or decreasing trend. Because of increases in other categories of migration, the proportion of family migrants fell from 27% of total inward migration in 1991 to 14% in 2016.

Asylum has been the smallest of the four main categories of migration since 2002, and made up 35,000 people or 6% of total long-term immigration in 2016.

Figure 2

Source: ONS, LTIM Estimates, Tables 2.04 and 1.01

A substantial proportion of migrants responding to the IPS do not provide a reason for migrating that can be categorised as work, family, study, or asylum. The ‘other’ and ‘no reason given’ categories, taken together, comprised an estimated 92,000 people in 2016. The dotted lines of Figure 2 show the LTIM data for the estimates of asylum applicants (labelled ‘Asylum’) and the author’s calculation of the remaining migrants (excluding asylum) who stated other/no reason for migrating (labelled ‘Other/No reason’). This calculation was made by assuming that asylum applicants are included in the groups of participants classified having “other” or “no reason” as their reason for migrating. The resulting figures are not endorsed by the ONS, and should be taken not as official data but merely as indicative of the possible composition of ‘other/no reason’ migrants. (For depiction of ONS data without this adjustment, see the Migration Observatory briefing on ‘Long-Term International Migration Flows to and from the UK’.)

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Trends are similar among non-EU migrants in different data sources

While LTIM/IPS data track reasons for migration for citizens of all countries, visa figures track only non-European migrants (or more precisely, non-EEA/Swiss nationals). Comparing immigration categories across these two data sources therefore requires a shift to focus exclusively on non-European nationals. Figures 3 and 4 show migration to the UK by category, with the two figures illustrating different data sets: the IPS and visa issuance data for non-EU nationals.

Figure 3

Source: ONS, LTIM Estimates, Tables 3.08a

Some differences between data sources exist, and this is expected because they measure slightly different things. In particular, IPS figures only count people moving or at least a year and therefore are expected to be lower than the number of visa issuances. In broad terms, however, they tell a coherent story. Both sources show study as the largest reason for non-EEA migration, followed by work then family.

Non EU/EEA migration in each category increased from the 1990s until the mid-2000s, when work and family migration to the UK began to decline. Student migration continued to increase in the second half of the decade, but fell significantly from 2011. For a more detailed discussion of data on each of the categories, see separate Migration Observatory briefings on ‘Non-European Student Migration to the UK’, ‘Non-European Labour Migration to the UK’, ‘Non-European Migration to the UK: Family and Dependents’ and ‘Migration to the UK: Asylum’.

Figure 4

Source: Home Office, Immigration Statistics, Table vi.04

Immigration of non-EU students (excluding dependents) increased significantly over the course of the 2000s. This trend is sharper in the IPS data in Figure 3, which shows the longest time span. IPS data show an 89% increase in entering students from 2005 to 2011. Visas issued to students (excluding student visitors of six months or less) increased by 58% in the period 2005-2009, with much of the increase concentrated in the one-year change from 2008 (232,000 visas) to 2009 (303,400). Numbers of student migrants then declined near the end of the decade, although the decrease takes place earlier in the visa statistics. The IPS shows that student migration of non-EU nationals to the UK dropped from 180,000 in 2011 to 92,000 in 2016.

Non-EU migration for work has also declined relative to its mid-2000s levels. Depending on the data source used, the decline stands at between 40% and 53% between 2005 and 2012; this is followed by an increase between 2012 and 2015. The decline in work-related migration in the IPS figures from 2015 to 2016 is not mirrored in the visa data.

According to IPS estimates, non-EU family migration has fluctuated over time, peaking in 2004 and 2006 at 74,000. Family visas obtained from the Home Office, which include EU/British family related migration show a 57% decline from a peak in 2007 (106,500) to 2016 (45,817).

Asylum increased until about 2002 and then declined, before slowly increasing again from 2007 onwards. Visas are not available for seeking asylum and so are not included in the visa data. (See the Migration Observatory briefing on ‘Migration to the UK: Asylum’ for more detail, including administrative data.)

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Evidence gaps and limitations

The existing evidence base on migration by category has several key limitations. Most important, there is a striking discrepancy between administrative sources and IPS estimates.
Several identifiable factors contribute to these differences but may not be sufficient for a full explanation (Migration Advisory Committee, 2010). First, the IPS uses the UK/UN definition of a migrant as someone staying in the UK for at least one year, while administrative data sources do not. The IPS includes a question asking arriving migrants and visitors how long they plan to stay in the UK; only those planning to stay for at least a year are counted as migrants. Visas and passenger entry data do not attempt to systematically exclude people arriving for less than twelve months, and include an unknown number of arrivals who will not stay long enough to qualify as migrants. ONS publishes data on short-term migration (between one and twelve months stay), but these are not directly comparable to administrative sources.

Second, visa data include people who never come to the UK, despite having legal permission. There are no reliable data on this number. A report on international students (Home Office 2010b) found that 20% of prospective foreign students issued Confirmation of Acceptance for Studies had no record of ever coming to the UK. But this figure was drawn from a non-representative sample of educational institutions, so one cannot be confident in generalising it to all students.

IPS estimates are not exact counts of migrants but have margins of error. For overall 2016 long-term immigration estimates, the margin of error was +/- 34,000 migrants, or +/- 5.7%. Rather than quoting a precise figure of 589,000 (prior to adjusting for asylum and other factors), it is more accurate to say that IPS estimates allow for 95% confidence that immigration fell between 555,000 and 623,000.

It is also worth noting that IPS/LTIM data do not match up with more accurate Census estimates of the contribution of net migration to the population over the course of the ten year periods between Censuses in 2001 and 2011. LTIM estimates underestimated net migration between 2001 and 2011. The ONS is aware of the shortcomings of these data and recently announced plans to further improve their quality (ONS, 2017).

Administrative data sources have weaknesses as well. They exclude EEA/A8 and British nationals, who make up a portion of official immigration estimates from ONS – about 55% in 2016. Administrative data also do not match up well with the official definition of a migrant, especially in terms of length of stay.

And, while visa data reflects actual counts of visas issued, passenger entry data provide only estimates based on a selected sample of landing cards rather than a complete count. Because sampling techniques changed in 2003, trends dating back past this change are not reliable (Home Office 2010a: 105, n1.3).

In addition, no data set perfectly categorises all migrants by category. IPS, relying on self-reporting, is left with some percentage who do not give a reason that can be coded into the standard categories (16% of overall immigration in 2016). IPS also does not capture many asylum seekers with its interviews, leaving ONS to use administrative data on asylum applications for its LTIM series estimates.


  • Home Office. “Control of Immigration: Statistics United Kingdom 2009.” Home Office Statistical Bulletin, Home Office, London, 2010a.
  • Home Office. “Overseas Students in the Immigration System: Types of Institution and Levels of Study.” UK Border Agency, Home Office, London, 2010b.
  • Home Office. “Control of Immigration: Statistics United Kingdom 2006.” Home Office Command Paper, Home Office, London, 2007.
  • Migration Advisory Committee. “Limits on Migration: Limits on Tier 1 and Tier 2 for 2011/12 and Supporting Policies.” UK Border Agency, London, 2010.
  • ONS. “Methods used to revise the subnational population estimates for mid-2002 to mid-2010.” Office for National Statistics, Newport, April 2013
  • ONS. “Quality of Long-Term International Migration Estimates from 2001 to 2011.” Office for National Statistics, Newport, April 2014.
  • ONS. “Quality of Long-Term International Migration Estimates from 2001 to 2011: Executive Summary.” Office for National Statistics, Newport, April 2014.
  • ONS. “International migration data and analysis: Improving the evidence.” Office for National Statistics, Newport, February 2017.

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