Who Counts as a Migrant? Definitions and their Consequences

25th August 2015
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Rob McNeil

This briefing considers the different ways in which one can understand who counts as a migrant in the UK and the implications of using different definitions.

Key Points

  • Definitions of 'migrant' vary among different data sources, and between datasets and law. Among other possibilities, migrants may be defined as foreign-born, foreign nationals, or people who have moved to the UK for a year or more.
  • Different definitions have significant consequences for data, both in terms of numbers of migrants (stocks and flows) and for the analysis of the impacts of migration.
  • The use of the term 'migrant' in public debate is extremely loose and often conflates issues of immigration, race/ethnicity, and asylum.
  • Conflicting definitions pose challenges for policy, particularly since many 'migrants' are not subject to immigration control and legislation.
  • When defined by intentions of a longer-term length of stay, more migrants have been leaving the UK than arriving in the UK.

Understanding the evidence

While most of the briefings in this series contain two sections Understanding the evidence and Evidence gaps and limitations designed to introduce readers to key concepts and terms that allow one to understand the data and analysis and to see where the available information is incomplete or limited, this entire briefing looks at the complexities of understanding the key definition in migration - that of a 'migrant'.


There are many ways to interpret the term 'migrant'

When counting migrants and analysing the consequences of migration, who counts as a migrant is of crucial importance. Yet there is no consensus on a single definition of a 'migrant'. Migrants might be defined by foreign birth, by foreign citizenship, or by their movement into a new country to stay temporarily (sometimes for as little as a year) or to settle for the long-term. Some analyses of the impact of migration even include children who are UK-born or UK nationals, but whose parents are foreign-born or foreign-nationals, in the migrant population. None of these definitions are equivalent, and none fit precisely with 'migrant' defined as an individual who is subject to immigration controls. Moreover, in the UK 'immigrant' and 'migrant' (as well as 'foreigner') are commonly used interchangeably in public debate and even among research specialists, although dictionary definitions distinguish 'immigrants' - people who are or intend to be settled in their new country - from 'migrants' who are temporarily resident. (In addition, in some scholarly and everyday usage, people who move internally within national boundaries are called migrants.)

Migrants in law

There is no definition of 'migrant' or of 'immigrant' in law, but there is a key distinction between those who have the 'right of abode' in the UK (all British citizens, but including a small minority of Commonwealth citizens) and those who do not have this right.

Those without the right of abode have in the past been largely the same as 'Persons Subject to Immigration Control', meaning that they need permission to enter or to remain in the UK. However, the numbers of people who are not 'subject to immigration control' but do have 'right of abode' have increased significantly in recent years, most notably EU nationals.

But if a migrant is not necessarily 'someone subject to immigration control', what alternative definitions exist?

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Migrants in datasets

Different datasets - and analyses from these datasets - use a variety of definitions of 'migrant', as shown in Table 1. These vary along several dimensions.

Country of birth: Analyses of the impacts of migrants on the UK economy usually define migrants as 'foreign-born'. These studies typically rely on the Labour Force Survey (LFS) and the Annual Population Survey (APS), comprehensive sources of data on workers and labour markets in the UK. This definition is consistent, and corresponds to a common understanding of migration. However, many foreign-born people are also British citizens, and thus would not count as migrants if defined by nationality, nor are they subject to immigration control.

Nationality: 'Migrant' alternatively may be defined as 'foreign national' using data from these sources. 'Foreign national' is also the definition of migrant used in data obtained from National Insurance Number (NINo) applications. This is viewed as more problematic, as nationality may change. Moreover, if self-reported, 'nationality' may be interpreted as describing an elective affinity dependent on social and cultural factors and personal feelings, rather than legal status.

Length of stay: In its analyses of migration flows into and out of Britain, the Office for National Statistics (ONS) uses the UN definition of 'long-term international migrant': "A person who moves to a country other than that of his or her usual residence for a period of at least a year [….] so that the country of destination effectively becomes his or her new country of usual residence". The main source of data on this is the International Passenger Survey (IPS), which is in turn the basis for ONS estimates of net migration. This definition is relevant to policy, as reducing net migration is a key policy objective of the current government, and the ONS estimate is the usual measure cited in policy discussions. But measuring migration according to this definition of ‘long-term migrant’ poses several challenges. First, for any given individual arriving in the UK, we do not know how long they will stay. IPS data are based on respondents’ intentions rather than recording what they actually do. In calculating its estimates of Long-Term International Migration (LTIM), the ONS attempts to adjust for 'switchers' - those who stay longer than intended or depart sooner than intended - but this is only an estimate and is also based on self-reports.

No other dataset presently available in the UK measures migration by the UN/ONS definition. Thus, other counts inevitably include people who live in the UK for less than 12 months, and do not qualify as migrants by this standard. Home Office administrative data gathered from immigration control processes can tell us how long newly-arrived potential migrants are entitled to stay, but cannot tell us whether they will depart early or extend their stay. Moreover, since data on departures from the UK are not available, it is not possible to determine actual length of stay retrospectively either – all that can be determined is when a migrant’s legal right to stay expires.

These differences translate into different estimates of the impacts of migration on the labour market, depending on the definition employed. For example, in 2013, 15.2% of those employed in the UK were foreign-born, while 9.3% were foreign nationals (see the Migration Observatory briefing "Migrants in the Labour Market: An Overview", Figure 2). Thus, if migrants’ share of the labour market is a concern for policy-makers, that share appears more than 60% larger if one considers all foreign-born workers rather than foreign nationals. On the other hand, the choice of definitions seems to make little difference when calculating unemployment rates among migrants (Coleman 2010).

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Table 1 - Definitions of migrant as represented in government data sources

UN definition (one year)Yes (self-reported intent)Can approximate with length of stay variableNo
Dictionary: "enter in order to settle"No (may be approximated with length of stay variable)Can approximate with length of stay variableYes, settlement grants
Subject to immigration controlYes, for those staying at least one yearCan approximate by excluding EU nationalsYes, with entry clearance visas, border entries
Foreign-born residentsN/AYes N/A
Foreign nationalsYes, for those staying at least one yearYesNo (includes non-EEA nationals only)

These different definitions of 'migrant' are not interchangeable. For example, people who are foreign born are not all foreign nationals; likewise, some foreign nationals may have lived in the UK for decades while others reside in the UK for only a year. Perhaps most importantly, not all foreign-born UK residents are subject to immigration control. Some are the children born abroad of UK national parent(s) - e.g. service personnel. Others are long-term British residents who have acquired citizenship. EEA nationals are also not subject to immigration control, yet are often considered migrants in public debate and in ONS net migration counts. This includes EEA nationals born outside the EEA.

In addition, 'migrant' is sometimes distinguished from, and sometimes includes, foreign nationals who are seeking asylum in the UK. These represent a small proportion of the overall entrants to the UK, though they have attracted a great deal of public and policy attention.

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Definitions and public debate

Who is a 'migrant' is often unclear in public debate. For example, migrants are often conflated with ethnic or religious minorities and with asylum seekers (Saggar and Drean 2001, Crawley 2009, Beutin et al. 2006, Baker et al. 2008).

Media discourses commonly use such terms interchangeably, particularly in tabloid newspaper discussions of asylum (Baker et al. 2008). Meanwhile the UK government’s official estimates of migration (ONS’ Long-Term International Migration estimates) include asylum seekers in counts of migrants entering the UK, while attempting to adjust the total numbers to exclude those who stay in the UK for less than a year and thus do not qualify as migrants defined by length of stay.

Public opinion surveys on immigration attitudes reflect, and may add to, this confusion. Some surveys do not define their terms, leaving respondents to answer questions based on their own implicit definitions. Other surveys define an immigrant as someone who has come to the UK 'to live' (Ipsos-MORI) or 'to settle' (2003 British Social Attitudes survey). These do not match the ONS definition, but they do fit the dictionary definition of immigration.

With such a variety of definitions and loose usage, there is not a straightforward mapping of migration data onto the subjects of public debate and concern. For example, some evidence suggests that, when used by employers, 'migrant' may signify recent arrivals rather than foreign-born, or even foreign national (Anderson and Ruhs 2010). For another, data gathered using a rigorous definition of 'migrant' may include groups who are not generally thought of in public debate as migrants - after all, famous British people such as Joanna Lumley, Cliff Richard, and even Prince Philip are foreign-born. Finally, the Migration Observatory’s  public opinion survey research shows that members of the public who want to see immigration reduced are more likely to focus on certain types of migrants - especially 'illegal' immigrants but also asylum seekers, extended family members, and low-skilled workers among those with legal status. Other types of immigrants such as students and high-skilled workers also are counted in immigration statistics, but have been of less concern in public opinion.

The existence of multiple definitions poses a particular problem for consistency in public debate regarding the number or impact of migrants, as the same discussion might simultaneously draw on two different definitions to suit the author’s purposes. For example, in discussions of migrants’ fiscal impact, concerns about 'migrants' aging and drawing pensions in the UK indicate a focus on migrants who settle permanently, yet discussions raising this concern often invoke LTIM statistics on the number of migrants to the UK. These statistics use the UN/ONS definition which includes arrivals planning to stay for as little as a year, and who are thus unlikely to ever draw a UK pension.

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Why does is it matter?: Policy challenges

The definition of 'migrant' is not simply a technical problem, but has an important effect on migration data and analysis generated from such data. This in turn has an impact on public understanding and on policy debates. The confusion in public debate over the definition of 'migrant' poses challenges for government policy. Not all those who are considered 'migrants' in public debate or in datasets are subject to immigration controls or immigration policy. The definition of 'migrant' used by most official sources includes many British citizens and others whose right to work and access to services in the UK are not determined by immigration controls alone. Thus immigration policy in itself cannot limit the rights of EU citizens to reside and claim benefits in the UK, for instance.

These are matters of European and foreign policy, not only immigration control. For example, consider the headline "Foreign Legions on Dole" (published in the Star on 20 January 2012). It seems implied that these 'foreigners' do not or ought not to have an equal right to claim benefits in the UK. One might assume that these are foreign nationals, whose entry can be based on fulfilling needs in British labour markets, with British citizens having priority. But, in fact, the data cited in this headline come from a government study of individuals who were non-UK nationals at the time when they registered for National Insurance numbers, and thus include naturalised British citizens who have a right to work in the UK and access the labour market and state benefits without discrimination.

Why does it matter? Data and analysis

Definitions also affect data, including measures of measuring both stocks (the number of migrants in the country at any given time) and flows (people moving into or out of the country) of migrants. For example, different definitions of 'migrant' yield different estimates of net migration flows. Current official government estimates (LTIM, based on the IPS) include several groups that would be excluded under other definitions. First, the IPS views all people of all nationalities as migrants, including UK nationals as well as EU nationals, so long as they are crossing national boundaries with the intent of staying for at least one year. Yet UK nationals obviously would not be considered migrants if defining migrants as 'foreign nationals'; EU nationals are migrants in this definition, but not if migrants are defined as those subject to immigration controls.

Figure 1 examines ONS long-term migration estimates by citizenship, showing that non-British EU nationals (not subject to immigration control) accounted for 178,000 in the net migration estimate for 2014 (meaning that 179,000 more migrants with non-British EU nationality arrived than departed within the calendar year). (This number increased greatly with the A8 accession of new EU member states in 2004, and has fluctuated considerably since then.) On the other hand, including British nationals in net migration statistics actually reduces the total, since more depart than arrive.

Figure 1

Note: ONS revised the total net migration estimates for 2001-2011 based on evidence that original figures had underestimated net migration. However, a revised version of inflows and outflows as well as breakdowns by citizenship is not currently available, This means that figures before and after 2011 are not directly comparable.

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Defining 'immigration' using length of stay or intent to settle as a key requirement has the potential benefit of distinguishing long-term migration from the more temporary churn of students, temporary workers, and others who come and go within a few years. Net migration flows look strikingly different when focusing only on those who plan to stay for more than four years. According to LTIM estimates, the UK has been experiencing negative net immigration for many years among those intending to stay in the UK or stay away for more than 4 years (see Figure 2). In 2012, ONS estimates that 144,000 people arrived in the UK intending to stay for more than 4 years, while 196,000 left the UK intending to stay away for more than 4 years. (Note that this is not inconsistent with a rising population of foreign nationals - migrants who stay between 1 and 4 years add to the resident population while they are here, and the number of such arrivals has increased since 2000. In addition, these figures are based on intended length of stay, which does not always match with what people actually do.)

Figure 2

In addition, some people subject to immigration controls are not migrants by UN/ONS definition. Many people come to the UK and are subject to immigration controls (i.e. require visas), but do not stay long enough to count as migrants under the length-of-stay definition. These groups include students on 6-11 month stays and temporary workers who leave within a year (see the Migration Observatory briefing "Short-Term Migration in the UK: A Discussion of the Issues and Existing Data").

For other analytical purposes such as assessing economic impact, usually done with the LFS/APS, different definitions again yield different estimates. In particular, the foreign-born population is larger than the foreign-national population. Foreign-born British citizens may have lived in the UK for decades and thus might not be relevant for discussions of the impact of present-day migration. In 2013, an estimated 12.5% of the UK population was born abroad, but 7.9% of the population was both foreign born and of foreign nationality, meaning that another 4.6% of the population were British nationals but born outside the UK (see the Migration Observatory briefing "Migrants in the UK: An Overview", Figure 3).

These differences translate into different estimates of the impacts of migration on the labour market, depending on the definition employed. For example, in 2013, 15.2% of those employed in the UK were foreign-born, while 9.3% were foreign nationals (see the Migration Observatory briefing on 'Migrants in the Labour Market: An Overview', Figure 2). Thus, if migrants’ share of the labour market is a concern for policy-makers, that share appears more than 60% larger if one considers all foreign-born workers rather than foreign nationals. On the other hand, the choice of definitions seems to make little difference when calculating unemployment rates among migrants (Coleman 2010).

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  • Anderson, B. and M. Ruhs, “Migrant Workers: Who Needs Them? A Framework for the Analysis of Staff Shortages, Immigration, and Public Policy.” In Who Needs Migrant Workers? Labour Shortages, Immigration and Public Policy. Oxford: OUP, 2010.
  • Baker, P., C. Gabrielatos, M. Khosravinik, M. Krzyżanowski, T. McEnery, and R. Wodak. “A Useful Methodological Synergy? Combining Critical Discourse Analysis and Corpus Linguistics to Examine Discourses of Refugees and Asylum Seekers in the UK Press.” Discourse & Society 19 (2008): 273-306.
  • Beutin, R., M. Canoy, A. Horvath, A. Hubert, F. Lerais, P. Smith, and M. Sochacki. “Migration and Public Perception.” Bureau of European Policy Advisers (BEPA), European Commission, Brussels, 2006.
  • Coleman, J. “Employment of Foreign Workers: 2007-2009.” Office for National Statistics, London, 2010.
  • Crawley, H. “Understanding and Changing Public Attitudes: A Review of Existing Evidence from Public Information and Communication Campaigns.” The Diana Princess of Wales Memorial Fund, London, 2009.
  • Saggar, S. and J. Drean. “Public Attitudes and Ethnic Minorities.” Cabinet Office Performance and Innovation Unit, London, 2001. www.cabinetoffice.gov.uk/strategy/downloads/files/british.pdf.

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