This briefing looks at citizenship and naturalisation among migrants in the UK. It provides data on how many migrants become UK citizens and how this varies for different migrant groups, as well as the factors that affect naturalisation.
- In 2019, 39% of people born abroad reported that they were UK citizens, but this share was higher for non-EU born (54%) than for EU-born (16%) migrants.
- Migrants from EU countries are less likely to apply for UK citizenship than those from outside the EU, although applications of EU citizens increased after the EU referendum 2016.
- An estimated 72% of non-EU migrants with permanent status (ILR) in the UK 10 years after getting their initial visa have become British citizens.
- Migrants who come to the UK with a family entry visa become citizens faster than those entering with a work or a study visa.
- There is evidence that naturalisation can improve migrants’ economic and social integration, especially among those from disadvantaged groups.
- Non-EU citizens from high-income countries (e.g. US, Canada or Australia) are less likely to become UK citizens than those from lower-income countries.
- People who moved to the UK as children are more likely to be British citizens, and this trend is particularly clear among the EU born.
- In 2019, there were an estimated 1.1 million non-UK citizen children living in the UK, of whom approximately 470,000 were born in the UK.
- Citizenship fees and language and integration requirements may create barriers to becoming a UK citizen.
- Around 3% of citizenship applications were refused in 2020, the most common reason being not meeting the ‘good character’ requirement.
- Non-EU born migrants are more likely to be citizens of the country where they reside in the UK (74%) than in EU-14 countries (58%).
- In 2019, 39% of people born abroad reported that they were UK citizens, but this share was higher for non-EU born (54%) than for EU-born (16%) migrants.
Understanding the Policy
What is citizenship? Citizenship has been defined in different ways, including ... Click to read more.
… as a legal status, a source of rights and an indicator of identity (Joppke, 2007). From a legal perspective, citizenship is a status that identifies a person’s formal membership of a state, entitling them to hold a country’s passport. Citizenship gives people certain rights, such as the right to vote in general elections (although Commonwealth citizens in the UK can vote without being UK citizens). Citizenship and naturalisation are also sometimes seen as an indicator of identity and belonging, or of social integration (Joppke, 2010; Ndofor-Tah et al, 2019).
While citizenship has a specific legal meaning, the concept is sometimes used much more broadly to refer to people’s national identity, civic engagement or social contributions, such as volunteering or participating in political protest. This briefing examines citizenship from a legal perspective. (The Migration Observatory briefing, The social relationships of migrants in the UK provides information about migrants’ civic participation in British society.)
Citizenship vs. permanent status
It is important to distinguish citizenship from permanent residence or settlement –Indefinite Leave to Remain (ILR), or Settled Status (for residents who applied through the EU Settlement Scheme)–, as these different statuses are often conflated in public debate. Migrants in the UK who are foreign nationals can acquire the right to live in the UK permanently without becoming citizens. Non-UK citizens who have permanent residence or settlement have extensive rights similar to those of UK citizens; for example, there are no restrictions on their right to work. Some settled migrants live their whole lives in the UK without becoming citizens. However, becoming a British citizen brings certain additional rights. In addition to voting, it is much harder for the government to deport citizens, and citizenship cannot be lost as a result of long absences from the country. There are also some specific restrictions on the jobs certain non-UK citizens can do in the public sector: most non-EU citizens who are not from the Commonwealth cannot work in the Civil Service or the Armed Forces, for example.
Becoming a UK citizen: naturalisation, registration and automatic acquisition
There are three main ways of becoming a UK citizen: automatic acquisition at birth, registration (usually for children), and naturalisation (usually for adults).
Almost all migrant adults without a British parent will have to naturalise in order to become UK citizens. Adult migrants who apply for citizenship must usually have lived in the UK for at least five or six years and must already have the permanent right to live in the UK (i.e. ILR for non-EU citizens and permanent residence or settled status for EU citizens). Applicants must meet a language requirement and pass the ‘Life in the UK’ test, which is designed to evaluate their knowledge of UK institutions, history and culture. The level of English language required for citizenship is ‘intermediate’, which is considered sufficient to have conversations about a range of familiar topics, but not necessarily enough to function fully in an English-speaking workplace. Applicants must have ‘good character,’ which includes paying taxes and not having a recent criminal record. They must also have been physically present in the UK for most of the previous three to five years. For a more detailed overview of naturalisation requirements, see Halliday (2019).
Citizenship applicants must pay a fee, which in 2020 was £1,330 per person, or £1,012 per child for children born in the UK to parents who are not UK citizens or settled residents. This is in addition to fees already paid for settlement, which are discussed in the Migration Observatory briefing, Migrant settlement in the UK.
Children who are born in the UK are not necessarily UK nationals. They will automatically be UK citizens if at least one of their parents is either a UK citizen themselves or a settled or permanent resident here; these children do not need to apply for citizenship but can apply directly for a passport. UK-born children can also register for citizenship if their parents receive either ILR or citizenship or if they have lived in the UK until the age of 10. Unlike for adults, there are some circumstances in which children can become citizens without first applying for ILR; this includes certain children without legal residence status, if they meet the conditions (e.g. if they have lived in the UK for a long time).
Understanding the Evidence
This briefing relies on Migration Observatory analysis of data from ... Click to read more.
… the Home Office (Migrant Journey data 2020), the Annual Population Survey (APS) 2019, collected by the Office of National Statistics (ONS), and the EU-Labour Force Survey 2019, collected by all EU member states as well as Iceland, Norway and Switzerland
Due to the coronavirus pandemic, face-to-face interviewing was suspended on the 17 March 2020 and respondents have been interviewed by telephone ever since. This change in the mode of data collection impacted the survey response rate, which has been significantly lower, and the non-response bias (that is, the profile of people who do not participate in the survey has changed). The ONS provided revised data with new population weights in 2021 in an effort to address the impact of the pandemic (see Office for National Statistics, 2021b). However, we use APS/LFS data 2019 for this briefing, as we consider them to be more reliable than 2020 and 2021 data, especially for analyses by region of birth.
Home Office records are used to analyse the numbers of people becoming citizens. For non-EU citizens, they are also used to examine migrants’ pathways to citizenship, including the visas people entered the country on before receiving ILR and citizenship. This makes it easier to estimate the share of settled residents who become citizens among non-EU migrants compared to EU migrants.
The APS data is used to look in more detail at the characteristics of people who do and do not hold UK citizenship. However, there are some very important limitations in this data:
- Citizenship is self-reported (or reported by parents/guardians for respondents under age 16), and it is possible that some people do not know their own citizenship status or the status of their children.
- The APS only captures one citizenship, but many people are dual citizens. The citizenship that is recorded in the APS is the first citizenship mentioned by respondents, which means that the APS is likely to underestimate the number of migrants who have naturalised (i.e. some people recorded as non-UK citizens will in fact hold dual citizenship).
- The APS does not tell us how respondents became UK nationals (e.g. via naturalisation, registration, or automatically). Most UK citizens who were born abroad will be people who migrated to the UK and later naturalised, but this category will also include people who were automatically UK citizens at birth because their parents were UK citizens.
The APS data are nonetheless useful for several purposes, such as comparing approximate shares of UK citizenship holders across groups; this comparison relies on the assumption that the order in which respondents specify their nationalities does not substantially depend on their other characteristics. Note that there are small differences between the APS data analysed for this briefing and the published ONS tables, because the definitions of country groupings provided in the data files for research use are slightly different.
Margins of error in the estimates
Because the APS and the EU-LFS are surveys and rely on samples, the estimates come with margins of error. This means that small differences between numbers or percentages may not be statistically significant. However, all the differences between groups that are described in the text of the briefing are all statistically significant. A difference between two groups is considered statistically significant when the probability that this difference is caused by chance is very small. In that case, we assume that the differences we observe in the data are likely to exist in the population. Note that small differences between estimates for different groups may not be statistically significant, if they are not described in the narrative of the briefing.
In 2019, 39% of people born abroad said that they were UK citizens, but this share was higher for non-EU born (54%) than for EU-born (16%) migrants
In 2019, 39% of people born abroad said that they were UK citizens (Figure 1), according to self-reported official survey data (see ‘Understanding the Evidence’ section above for important limitations of this information, which is likely to understate rates of citizenship acquisition). This share was higher (50%) for those who had been in the country for at least 6 years (since 2013, using 2019 data) and thus were more likely to be eligible to naturalise.
EU-born migrants (16%) are less likely to say that they have British citizenship than those born in a non-EU country (54%). A consequence of this is that non-EU born migrants make up the majority of people born abroad in the UK (62% or 5.8 million in 2019), but non-EU citizens only represent an estimated 39% (2.5 million) of all foreign citizens living in the UK in 2019.
Migrants from EU countries are less likely to apply for UK citizenship than those from outside the EU, although applications of EU citizens increased after the EU referendum 2016
Multiple factors affect migrants’ desire and ability to become citizens of the country they have moved to, ranging from the desire for recognition as a full member of society and the right to vote, legal certainty about their residence rights, pragmatic advantages (e.g. easier travel), to a symbol of status (see e.g., Aptekar, 2016; Birkvad 2019; Harpaz and Mateos, 2019; Rutter et al, 2008). Reasons for seeking citizenship are not necessarily ‘positive’ and can include migrants’ fears of poor treatment or discrimination (Sigona and Godin, 2019; Aptekar, 2016).
Some groups of migrants are more likely to apply for the citizenship of countries where they reside than others. For example, migrants from developing or politically unstable non-EU countries are more likely to naturalise than other foreign nationals, as well as those who are long-term residents or who speak the destination-country language (Dronkers and Vink, 2012). Migrating at a younger age or having a partner who is a citizen of the destination country has also been linked to a higher likelihood of naturalisation (Peters et al., 2016). Policies are also thought to play a role, and countries with more liberal citizenship polices tend to have a higher share of naturalised migrants (Dronkers and Vink, 2012), as discussed further below.
In the UK, EU citizens have been less likely to become UK citizens than people from non-EU countries (Figure 2). There are various possible reasons for this. EU citizens may have felt more secure in their immigration status because of the protections offered by EU law, and thus felt that becoming a citizen was not necessary (Moreh et al., 2018). Barriers in the process may have played a role: all people applying for citizenship must already have proof of their permanent status, but until recently the process for most EU citizens to get such a document was quite complex (Migration Observatory, 2016). Most EU citizens will also not have had any contact with the immigration system until recently (due to their application to the EU Settlement Scheme), whereas non-EU citizens will generally have already had to submit multiple applications (for entry visas, renewals and indefinite leave to remain), making them more familiar with the process.
Scholars have argued that political and economic instability in the last ten years have made EU citizens living in other EU states more likely to become citizens than before (Graeber, 2016; Moreh et al., 2019). A recent study based on interviews with EU migrants, for example, found that EU citizens often saw becoming British as a way to ‘escape the negative stigma’ they felt was attached to being a migrant (Sigona and Godin, 2019).
After the Brexit referendum, the number of EU citizens granted UK citizenship increased sharply from previously low levels. From 2011 to 2015, an average of nearly 14,000 EU citizens became UK citizens each year, and by 2021 this had increased to around 57,600 (Figure 3). However, EU citizens represented only 30% of all successful applications in 2021, while they made up 59% of foreign national residents in the same year (authors’ calculations based on APS 2021).
Citizenship applications fell in 2021 for the first time since 2014 among EU-14 (10% decrease), EU-2 (6% decrease) and EU-8 citizens (10% decrease) (Figure 3). Citizenship grants to EU citizens fell in 2020 and 2021. This may result in part from slower processing of applications and the cancellation of citizenship ceremonies during the pandemic.
Interestingly, Irish citizens applied for citizenship in larger numbers following the referendum, even though they retain rights to live and work in the UK despite Brexit. Citizenship applications from Irish nationals more than tripled from 2015 to 2021 (173 to 515 applications), albeit from a low base (Home Office Immigration Statistics December 2021, table cit_d01).
The majority of non-EU migrants who are still in the UK 10 years after getting their initial visa will have become British citizens
The longer people have lived in the UK, the more likely it is that they will have become a UK citizen. The majority of non-EU migrants with more than 10 years of residence are British citizens (Figure 4). For example, among non-EU citizens granted entry visas in 2007, 63% had become UK citizens by the end of 2016 and 74% by the end of 2020 (Figure 4). The shares are slightly higher (72% by 2017 and 78% by 2020) if we exclude people who do not have ILR and thus will usually be ineligible for citizenship.
Migrants who come to the UK with a family entry visa receive citizenship faster than those entering with a work or a study visa
The time it takes to become a citizen varies depending on how the person qualified to come to the UK initially (Figure 5). This is primarily because the route to permanent settlement or ILR (which is required before citizenship) is longer for some groups, such as international students. For example, among people granted entry visas in 2007 and whose visas had not expired, family members tended to become citizens the fastest, with 60% already UK citizens by the end of 2013. International students took longer to become British citizens, but the gap narrowed significantly after 10 years since arrival – so by 2020 the overall the share of UK citizens was 59% among those who moved to the UK with a student visa in 2007, while this percentage was 76% and 74% among those who came with a family and a work visa, respectively (Figure 5). This mirrors the trends in settlement statistics, where we also see that non-EU students take longer to get ILR, as shown in the Migration Observatory briefing, Migrant settlement in the UK.
Evidence suggests that becoming a citizen may help migrants’ economic and social integration, especially among those from disadvantaged groups
In policy discussions, citizenship is often seen as something that can help migrants to integrate. For example, the Home Office Indicators of Integration Framework describes citizenship as an “important bedrock to the integration of any individual in a society” (Ndofor-Tah et al., 2019: 18).
However, there is an ongoing political debate about the role of naturalisation on migrants’ integration. On one hand, some have argued that it should not be too easy to become a citizen, or that citizenship policy should be a ‘reward’ for integration. For example, a government-commissioned review of citizenship in 2008 suggested that “the requirements for the acquisition of citizenship should stimulate integration and civic participation as well as constitute proof that those processes are taking place to existing citizens” (Goldsmith, 2008).
On the other hand, there is some evidence that becoming a citizen has a positive impact on economic and social integration, suggesting that high barriers to citizenship could make integration harder. For example, the OECD (2011) found that naturalisation improved the labour market outcomes of many groups of foreign nationals in France, Germany, Sweden and the United States, particularly for the most disadvantaged.
A study from Switzerland shows positive effects of naturalisation on social integration (measured by a combination of factors such as planning to stay permanently, local club membership and reading local newspapers), with the largest effects for traditionally marginalised migrant groups (Hainmueller et al., 2017). Another study found that, in Germany, faster access to citizenship improved the economic situation of migrant women, and that migrants with shorter residency requirements for citizenship were more likely to invest in language and vocational training (Gathmann and Keller, 2018). However, such findings are not universal. For example, Bartram (2019) found that becoming a citizen did not increase measures of political participation among migrants in the UK.
Among the top countries of origin for non-EU citizens, people from higher-income countries are in general less likely to be UK citizens 10 years after arrival than those from lower-income or politically unstable countries. For example, among non-EU citizens granted entry visas for work, family or study between 2007 and 2010 and who were settled (i.e. with ILR) in the UK by 2020, over 85% of those from Iraq and Afghanistan were citizens, compared to 33% of those from South Korea, 45% from the US and 47% from Canada (and despite the fact that these three countries allow dual nationality) (Figure 6).
This is consistent with trends found across EU countries (Dronkers and Vink, 2012), and is thought to be because migrants from lower-income countries perceive the relative benefits of taking on a nationality from a high-income such as the UK to be higher. For example, some citizenships provide greater travel freedom, or the ability to live in a country with high economic prosperity, stability and human development (Kochenov and Lindeboom, 2017).
People who moved to the UK as children are more likely to be British citizens, and this trend is particularly clear among the EU born
Both EU- and non-EU-born migrants who moved to the UK when they were children (especially those who moved at age 5 or younger) are more likely to be UK citizens than people who moved later. This is partly because people who moved to the UK when they were younger are more likely to have been in the UK for longer than those who moved at older ages. Figure 8 takes this into account and presents the share of UK nationals among migrants who came to the UK at different ages, but keeps their years of residency in the UK constant (i.e. that is, we show the relationship between age of migration and being an UK national that is unrelated to years of residency in the UK). This confirms previous research showing that migrants who migrate at younger ages are more likely to become citizens (Peters et al., 2016; Chiswick and Miller, 2009). Among people who moved to the UK as adults, however, the likelihood of being a UK citizen is unrelated to their age of migration (Figure 7).
In 2019, there were an estimated 1.1 million non-UK citizen children living in the UK, of whom approximately 470,000 were born in the UK
UK-born children are not necessarily automatically British nationals. See the Home Office Registration as a British citizen: children for detailed information about the process of becoming a UK national for minors. In 2019, there were an estimated 1,140,000 children under the age of 18 who were not British citizens living in the UK, the majority of whom were EU citizens (Figure 8). Among children with EU citizenship, an estimated 48% (362,000) were born in the UK. Among non-EU citizen children, the share was lower: 27% or 108,000. Note that children’s citizenship in the APS data is usually reported by their parents, and in some cases the parents may not know whether their children are UK citizens because of the complexity of citizenship rules (see ‘Understanding the Policy,’ above).
Citizenship fees and language and integration requirements may create barriers to becoming a UK citizen
Citizenship fees in the UK are high compared to many other countries. According to the Migrant Integration Policy Index (2020), non-EU citizens in the UK who want to settle permanently or become British citizens face among the highest costs in the developed world. Since 2018, the cost of an adult citizenship application was £1,330, up from £268 in 2005 (Figure 9). This compares to an estimated cost of £372 to process each application (Home Office, 2019), and the ‘surplus’ is used to fund other parts of the immigration system.
The effects of fees on the citizenship application rate is hard to measure, although a 2019 report by the Independent Chief Inspector of Borders and Immigration (ICIBI) documented concerns among lawyers, civil society and applicants about the impacts of high costs of citizenship registration for children in particular (ICIBI, 2019; see also Ealing Law Centre, 2014). EU citizens in the UK have cited the fee as a significant deterrent (Sigona and Godin, 2019), and evidence from the United States (where fees are lower) has found that fee subsidies significantly increased application rates (Hainmueller et al, 2018).
Language requirements and so-called ‘civic integration tests’ (e.g. Life in the UK test or the Civic Integration Exam in the Netherlands) also affect people’s ability to naturalise (see e.g. van Oers, 2014; Valdez-Symonds, 2019). For example, applications for naturalisations spiked in 2013 (179,000) and fell dramatically in 2014 (89,000)– a decrease of 50%–, most likely as a consequence of the introduction the knowledge of language and life requirements on 28 October 2013 (Figure 10). The decrease in naturalisation applications from 2013 to 2014 was particularly pronounced among applicants of certain nationalities, e.g. Nepal (-81%), Philippines (-79%), Bangladesh (-75%), Afghanistan, Turkey or Somalia (-67%) (Home Office Immigration Statistics December 2021, table cit_d01).
A recent study on migrants to Denmark, the Netherlands and Sweden found that after two decades in the destination country, the cumulative naturalisation rates of those migrants vary widely (+80% in Sweden, 67% in the Netherlands, and 37% in Denmark) (Vink et al, 2021). The authors partly attribute these country differences to the language requirements and integration tests introduced in the Netherlands and Denmark –but not in Sweden–, which particularly affected migrants with lower levels of education.
The pandemic also created administrative barriers to becoming a citizen. Approximately 171,000 people applied for citizenship in 2020, compared to 174,000 in 2019. However, grants of citizenship dropped from 159,000 to 131,000 over the same period (data from Home Office Immigration Statistics December 2021, tables cit_d01 and cit_d02). The gap between grants and applications was the largest since 2005 and may have been the result from the cancellation of citizenship ceremonies, which prevented many applicants from completing the citizenship process in 2020. The gap between applications and grants of citizenship decreased slightly in the first three quarters of 2021 (29,000), but it was still high compared to previous years (data on grants of citizenship for Q4 2021 not available at the time of writing).
Around 3% of citizenship applications were refused in 2020, the most common reason being not meeting the ‘good character’ requirement
In total, around 5,613 or 3% of citizenship applications were refused in 2020 (excluding withdrawn applications). The most common reason for refusal was not passing the ‘good character’ requirement (Figure 11). According to the Home Office, applicants for citizenship aged 10 or older will not be considered of good character if they have been involved in crime, have not paid their taxes, have been deliberately dishonest or deceptive in their dealings with the UK government, have breached immigration law or have been deprived of their citizenship before (Home Office, 2019).
Refusals data do not tell us what the main barriers to citizenship are for non-citizens in the UK; this is because we do not know how many foreign citizens have not applied because they believe that they will be refused or cannot afford the fees.
In Q3 2020, the pass rate for the ‘Life in the UK’ test was 80% (Home Office, 2020, table LUK_01). This figure by definition only includes those who took the test and does not show whether people were deterred from applying for citizenship because they believed they would be unable to pass the test.
Non-EU migrants in the UK are more likely to be UK citizens than non-EU migrants in other EU-14 countries are to be citizens of those countries
Non-EU/EFTA born migrants are more likely to be UK citizens (74% in 2019) than those in EU-14 countries are to be citizens of those countries (58%), when considering migrants with more than 10 years of residence. By contrast, EU/EFTA-born migrants are less likely to be citizens compared to EU/EFTA-born migrants living in EU-14 countries (Figure 12).
In general, countries with inclusive citizenship policies such as Sweden or Portugal tend to have higher shares of naturalised migrants (Figure 12). Favourable citizenship policies are typically considered to include factors like the recognition of dual nationality, automatic citizenship for those born in the country of residence, no more than 5-year residence requirement, free and flexible language courses and tests, low citizenship application fees, and security of status once granted (Migrant Integration Policy Index, 2020). Note, however, that the national composition of EU and non-EU migrants varies across EU-14 countries and the UK, and this could also explain some of the differences.
Figure 11 does not distinguish between the foreign-born who naturalised (i.e. acquired their country of residence citizenship by fulfilling certain requirements) from those whose citizenship has been recognised by descent (i.e. because their parents or ancestors were born in that country). In the UK, citizenship by descent is only possible for one generation. In other countries such as Germany, however, many ‘ethnic’ German communities living in the former Eastern bloc and the Soviet Union have been granted German citizenship automatically. This could explain the high share of EU-born German citizens in Germany (64%), which is slightly above the non-EU born (60%).
Evidence gaps and limitations
There is a major gap in the evidence about dual citizenship. As noted above, the UK’s main population survey (the APS) does not capture more than one citizenship and does not prioritise UK citizenship where a person has more than one. Some other data sources that do collect some information on dual citizenship only have information about the passport someone holds; however, a dual citizen may choose not to renew on of their passports if they do not need it to travel, so these figures are likely to understate the prevalence of dual citizenship.
Available data sources for the UK do not tell us when a person became a citizen (e.g. the year of naturalisation) or how they became a citizen (e.g. by descent or residence in the UK), which makes it harder to research the effects of becoming a citizen on individuals and families.
It is also very difficult to measure the impacts of specific policies related to naturalisation – for example, how many people are deterred from becoming a citizen because of the fees or language requirements. While qualitative research suggests that these policies could have an important impact, few studies have been able to produce a quantitative estimate of the effects (for exceptions, see Hainmueller et al, 2017 and Hainmueller et al, 2018).
Research for this briefing was funded by Paul Hamlyn Foundation, the Joseph Rowntree Charitable Trust, and Research England’s Strategic Priorities Fund (SPF) QR allocation. Thanks to Roxana Barbulescu and Jill Rutter for comments on a previous draft of this briefing. Thanks to Zachary Strain for research assistance.
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