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

09 Mar 2017

This briefing examines immigration by category. The analysis distinguishes between European and non-European migrants and among four basic types: work, study, family, and asylum.

  1. Key Points
    • Almost as many EU nationals as non-EU nationals migrated to the UK in 2015.
    • People moving for work made up the largest category of immigrants in 2015, while asylum was the smallest.
    • Asylum applicants constituted 5% of migration to the UK in 2015.
    • 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

    Passenger Survey (IPS) is conducted by the Office for National Statistics (ONS), Long-Term International Migration (LTIM) estimates derived from IPS, administrative data from entry clearance visas issued and passengers’ border entries recorded from landing cards at ports of entry. 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 administrative 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 and entry 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.

Almost as many EU nationals as non-EU nationals migrated to the UK in 2015.

This briefing discusses data on migration to the UK in terms of the categories of work, study, family, or asylum. Total migration to the UK (including British nationals) was 631,000 in 2015 according to LTIM estimates, as shown in Figure 1. Non-European migration made up 44%, or an estimated 279,000 migrants arriving. EU nationals were an estimated 43% of arriving migrants (269,000). The remaining 13% (84,000) were British nationals, who might have been born abroad or who might be returning to the UK after a prolonged absence.

Immigration patterns of non-EU, EU, and British nationals have followed different trends since 1991, as shown in Figure 1. Non-EU inflows increased from 1997 (166,000) until 2004 (370,000) before declining to 303,000 in 2009 and 248,000 in 2013. This was followed by an increase to 287,000 in 2014 and a reduction to 279,000 in 2015.

Estimated EU (non-British) migration to the UK increased at a slower rate from 1991 (53,000) until 2003 (66,000). It then increased sharply from 2004 following the accession of the A8 Eastern European countries to the EU, and rose to 198,000 in 2008. EU immigration slowed from 2009 to 2012, before rising again to 269,000 in 2015.

Among British nationals, migration to the UK has fluctuated over the last two decades. The total in 1991 (110,000) was actually larger than in 2015 (84,000). Because of this decrease and because non-British migration has increased during this period, British nationals comprise a decreasing share of total inward migration, falling from 33% of inward migration in 1991 to 13% in 2015. 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

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

Work is the most common reason for migration to the UK and asylum is the smallest LTIM estimates suggest that work was the most common reason given for migration to the UK in 2014, as shown in Figure 2. (“Work” combines two IPS 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 2014 and 2015, migration for work increased again to 278,000 and 308,000 respectively.

Migration for formal study increased from 87,000 (18% of total arrivals) in 2001 and peaked at 238,000 in 2010. It has been declining since then, albeit with a slight increase in 2014, reaching its lowest level since 2009 (175,000), at 168,000 in 2015.

Family migration fluctuated over the years, but has changed little in recent years, overall. However, there was a lower number of people coming to ‘accompany or join’ family members in 2015 (74,000) than in 1991 (90,000). Similarly, the proportion of family migrants fell from 27% of total inward migration in 1991 to 14% in 2015, although this is mostly because of increases in other categories and total immigration.

Asylum was the smallest of the four main categories of migration in 2015, with 30,000 people or 5% of total inward migration. Asylum has been the smallest of the four main categories since 2002.

Figure 2

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 82,000 people in 2015.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 similar among non-EU migrants in all data sources

While LTIM/IPS data track reasons for migration for citizens of all countries, visa and border admissions data track only non-Europeans migrants (or more precisely, non-EEA/Swiss nationals). Comparing immigration categories across data sources therefore requires a shift to focus exclusively on non-European nationals. Figures 3, 4 and 5 all show migration to the UK by category, with each figure illustrating a different data set: the IPS, visa issuance data, and border admissions data respectively for Non-EU nationals.

While some differences between data sources exist, together they tell a coherent story. 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 3

Figure 4

Figure 5

Immigration of non-EU students (excluding dependents) increased dramatically over the course of the 2000s. This trend is most clearly illustrated 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 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). All datasets then show a decline in the numbers of student migrants near the end of the decade, although the timing differs across the three sources. Border admissions data (Figure 5) seem to present a decline somewhat earlier, but this is due to significant changes by the Home Office in its collection and calculation of these figures in late 2007, when it began to track short-term student visitors separately and exclude them from the totals. The IPS shows that student migration of non-EU nationals to the UK dropped from 180,000 in 2011 to 112,000 in 2015.

Non-EU migration for work has also increased over the past two decades, but has declined since the mid-2000s. Depending on the data source used, the decline stands at between 39% and 52% between 2005 and 2012; this is followed by an increase between 2012 and 2015 regardless of the dataset used.

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 includes EU/British family related migration show a 55% decline from a peak in 2007 (106,500) to 2015 (47,500). Border admissions data also show a steady decline from 2010 onwards.

Asylum increased until about 2002 and then declined, before slowly increasing again from 2007 onwards. Asylum seekers (main applicants only) made up 5% of total annual immigration in 2015, as per LTIM estimates. (See the Migration Observatory briefing on ‘Migration to the UK: Asylum‘ for more detail, including administrative data.)

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Numbers of non-EU migrants are higher in administrative sources, but percentages by category are similar

As Figure 6 shows, all three data sources paint a similar pictureof the relative share of each category in 2015 inflows. In each source, students were the largest share, followed by work then family. Note that in this figure, all dependent visas and (accompanying) passenger entries are included in the family category. This is for comparability with IPS figures, where the family category includes both migrants who are coming to join family members (roughly corresponding to family route migrants) and also those who are accompanying a family member migrating for work or study (corresponding to dependents).

Figure 6

When viewed as raw numbers, the administrative sources count many more migrants in each category than the IPS estimates. This is discussed in more detail below.

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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.

Border admissions data include other anomalies. For example, 2010 admissions of work migrants exceed the number of visas issued, which is difficult to explain. Clandestine entries of workers without visas cannot explain the discrepancy, as both visas and passenger entries are administrative data that include legal, detected entries only.
The IPS and LTIM also have the inherent limitations of a sample survey.

IPS estimates are not exact counts of migrants but have margins of error. For overall 2015 long-term immigration estimates, the margin of error was +/- 33,000 migrants, or +/- 5.2%. Rather than quoting a precise figure of 631,000 (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 598,000 and 664,000.

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 2015. 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 (13% of overall immigration in 2015). 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. Meanwhile, border admissions data include a large number of arriving passengers in a residual category of “others given leave to enter,” which include asylum-related cases; people “of independent means, and their dependents”; and dependents of NATO forces (Home Office 2010a: Table 1.3, n10). In some publications, the “other” category also includes additional categories such as children and dependents (Home Office 2007: Table 2.2, n5). Visas match categories more completely, but are vulnerable to the problems mentioned


  • 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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