Naturalisation as a British Citizen: Concepts and Trends

30th August 2013
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Rob McNeil

This briefing gives details about how many foreign citizens acquire British citizenship every year, their demographic characteristics, and the various bases for their grants of British citizenship.

Key points

  • In 2012, 194,344 foreign citizens naturalised as British citizens, up from 177,878 in 2011 and from a five year average of 169,373 from 2006-2010.
  • English language requirements and the Life in the UK test account for a small percentage of rejected naturalisation applications, although these requirements may deter additional potential applicants.
  • 53% of naturalisations went to foreign nationals who have lived in the UK for the required five years, plus one additional year as a settled resident for non-EEA/Swiss nationals. Most of the other half is split between spouses and civil partners of British citizens and minor children registering as citizens.
  • Among British citizens naturalising in 2012 the largest groups by citizenship were from India (15% of the 2012 total), Pakistan (9%), Nigeria (5%), the Philippines, South Africa and China at (4%) each.

Understanding the evidence

Naturalisation is the acquisition of British citizenship by someone who held (or continues to hold) foreign citizenship. There are several routes to naturalisation. Adults may qualify for British citizenship through at least five years of residence in the UK, or through marriage to a British citizen (with three years’ residence in the UK as a spouse or civil partner). In addition to residency requirements, naturalising citizens must meet requirements of ‘good character’, ability to communicate in English (or Welsh or Scottish Gaelic), and ‘knowledge of life in the UK’ (as assessed by a Life in the UK test, also required for those applying for settlement). Children may qualify for either automatic or discretionary “registration” as British citizens depending on the country of their birth and nationalities of their parents. Home Office administrative data counts citizenship grants of each of these types. Though registrations are not technically naturalisations, at least in Home Office classifications, they are included with naturalisations in this briefing.
Home Office data include information on refusals of citizenship applications, including those refused because of a failure to demonstrate language proficiency or knowledge of life in the UK.
Note: Data prior to 2005 include grants of the “right of abode“ (a form of permission to live permanently in the UK) as a Commonwealth national; since 2005, this category, small in number, is recorded separately from naturalisations to British citizenship.

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Citizenship grants per year more than doubled since 2000

In 2012, 194,344 foreign citizens naturalised as British citizens, up from 177,878 in 2011 and from a five year average of 169,373 from 2006-2010. Grants of British citizenship have increased substantially since 2000, with annual averages of 114,284 from 2000-2004. The largest single year total was recorded in 2009 (203,790) but this seems to be the result of internal administrative matters; the Home Office reported that insufficient staffing to make decisions on citizenship application in 2008 led to a backlog of cases that began to be resolved in 2009 when staffing was increased (Home Office 2010: 1). Thus, the two-year average for 2008-2009 was 166,583, in line with the trend for that period.

Also worthy of note: the 1995-1999 period saw an especially low number of naturalisations, with an average of 45,886 per year. The 1997 total of 37,010 was the lowest annual total since the implementation of the 1981 British Nationality Act on 1 January 1983. Dating trends from that low point does not provide an accurate historical assessment.

The acceptance rate for naturalisation applications has increased as well. In 2012, 3.5% of applications ended in refusal or withdrawal, down from 3.9% in 2011 and 9.3% as recently as 2005 and from at least 10% for most of the 1990s (see Figure 1). Applications have been increasing as well, however, so that the reduced refusal rate does not account for a large share of the rise in naturalisations. The increased acceptance rates are at least partially the result of new application checking services that catch incomplete or inadequate applications before they are filed (Home Office 2010: 10).

Figure 1

Note: Calculations are based on refusals and withdrawals as a percentage of the total of grants, refusals, and withdrawals in a given year. They are not based on applications made in that year, because some decisions taken do not relate to applications received in the same year.

The trend in naturalisations has several notable spikes that can be explained as the result of changes to law or administrative procedures. In chronological order: 1974-1975 saw an increase in grants to Pakistanis following the Pakistan Act of 1973 (which created a temporary window for Pakistani nationals to register as Citizens of the United Kingdom and Colonies, after which naturalisation would be required as for non-commonwealth nationals). Next, the increase in 1989 comes from the opening of a new application processing centre in Liverpool, increasing administrative capacity. Finally, increases in grants through registration since 2003 may reflect new provisions in the Nationality, Immigration and Asylum Act 2002 (Home Office 2010: Table A notes).

The introduction of the Life in the UK test and more stringent English language requirements in 2004 does not seem to have changed the increasing trend in naturalisations. It is possible that there would have been even more naturalisations without these new requirements (including not only the newly-required knowledge and skill tests but also the fees required to prepare for and take them). Further, the language and knowledge requirements would seem to pose a disproportionate burden on nationals of poorer, less educated and non-English-speaking countries (Ryan 2008), and may have deterred applications among nationals of such countries.

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Residency, marriage, and children are the three main grounds for citizenship grants

As noted above, British citizenship grants are divided among three main categories: migrants fulfilling the five-year residency requirement, spouses and civil partners of British citizens, and underage children being registered as citizens. As seen in Figure 2, about half of grants overall come from residency requirements (53% in 2011, 50% from 2006-2010); the two family routes (marriage/civil partnership and children) account for slightly less than half combined (marriage/civil partnership: 20% in 2011, 22% 2006-2010; children: 24% in 2010, 25% from 2006-2010). The remaining 3% in 2011 were “other” bases for citizenship, including, for example, transfers from British overseas territories citizenship to full citizenship status.

Figure 2

Each of the main pathways to naturalisation (residence, marriage, and registration of minor children) has grown in numbers since 2000. Residence-related grants increased the most over the 2000s, both in number and in percentage terms. Grants from residence have increased from 34,980 in 2000 to 107,196 in 2012. Naturalisation through marriage almost doubled in the decade, from 27,425 in 2000 to 52,625 in 2009 but then decreased to 39,138 by 2012. Grants to minor children increased from 19,160 in 2000 to 42,980 in 2012. Since 2000 residence-related grants have grown from 43% of naturalisations in 2000 to 53% in 2012, while marriage-based grants declined from 33% to 20% in the same period. Minor children registrations constituted 23% in 2000 and 24% in 2012. “Other” categories increased slightly.

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India and Pakistan lead increases

The largest groups of newly naturalised UK citizens in 2012 had prior citizenship from India, Pakistan, Nigeria and South Africa (see Table 1); Asian nations also contributed the most to growth in naturalisations over time (see Figure 3). African nationals also contributed heavily to the growth in naturalisations in the 2000s. Nigeria, South Africa, Somalia and Ghana ranked among the top 10 prior nationalities of new UK citizens in 2012 (and in many previous years as well). Europe and the Middle East have also grown as sources of naturalising British citizens. Only the Americas have declined as a source region for naturalisations. Grants of citizenship to nationals of North and South American countries averaged 21,074 annually between 1983 and 1989 before dropping to only 4,855 annually in the 1990s and 10,710 annually since 2000.

Table 1 - Top ten nationalities as share of total, 2012

Country of previous nationalityshare of total
South Africa4%
Sri Lanka3%

Figure 3

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The demographic profile of naturalising citizens leans toward the young and female, as shown in Figure 4. In 2012, 41% of adults receiving citizenship were female. Including children, the distribution was 41% adult women, 39% adult men and 20% children.

Figure 4

By age group, adults aged 25-34 comprised the largest share of naturalising citizens (30% of the total). Only 14% were 45 and older; 22% were children aged under 18. Women outnumbered men primarily among young adults (16-24 and 25-34 age groups) as well as those aged 55 and over. The gender balance was close to even among children, and men outnumbered women in the 35-54 age groups.

Figure 5

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Legal barriers, language and integration, and poverty in origin country affect naturalisation rates

Naturalisation reflects both legal requirements and a personal choice on the part of a foreign national to apply to become British. Therefore, one might expect that naturalisation is more likely when there are few legal barriers, when naturalisation brings greater benefits, and when naturalising does not mean giving up much of value, such as a previous citizenship. Strands of research have investigated each of these aspects of the determinants of naturalisation rates.

First, naturalisation rates are indeed lower in nations that impose more legal requirements for acquiring citizenship. Traditionally, nations have been categorized as following one of two logics of citizenship: jus soli (literally “right of soil”) where citizenship comes from being born in the country, and jus sanguinis (literally “right of blood”) where citizenship comes from parents’ citizenship and in-country birth does not confer citizenship. Contemporary citizenship law in many nations blends the two logics in varying proportions.

Overall, British citizenship law is more open to naturalisation than traditional jus sanguinis nations such as Germany. However, although it may be viewed as the original jus soli country, it is now less open than other traditional jus soli nations such as the USA and Canada. In a comprehensive comparative study, Janoski (2010) identifies as many as 12 requirements that countries may impose; British citizenship law now includes many from this list (Sawyer 2009). These barriers to naturalisation include requirements of good conduct, language skills, efforts toward cultural integration (measured in the form of the Life in the UK test), years of residency, and navigation of complex and expensive application procedures.

The “good character” requirement accounts for an increasing number of rejected applications for naturalisation, rising to 37% of all refusals in 2012 (from 10% to 13% in the years immediately preceding legal changes to this requirement in 2008). Failure to demonstrate language proficiency or knowledge of life in the UK comprised 2% of refusals (382 people), as shown in Table 2. The most common reason for refusal was the failure to meet the “good character” requirement.

Table 2 - Reasons for refusal, naturalisation applications, 2012

Reasons for refusalshare of total
Not of good character37%
Incomplete applications10%
Parent not a British citizen8%
Delay in replying to enquiries from UKBA5%
Insufficient Knowledge of English and KOL2%
Oath not taken in time0%

Source: Citizenship data tables Immigration Statistics, Oct-Dec 2012, Table cz.09"

On the other hand, British citizenship law does not have many jus sanguinis characteristics, making it relatively easy for children born in the UK to non-British parents to be registered for British citizenship. British citizenship law also does not require renunciation of prior citizenships in order to naturalise. (Law in the sending nation is relevant here as well. Zimbabwe, for example, has not permitted dual citizenship, probably lowering naturalisation rates for Zimbabwean migrants to the UK.)

Research on the individual determinants of naturalisation—the ways in which the costs and benefits to individuals determine their likelihood of naturalising—has been conducted mainly in North America and not in the UK (Bloemraad 2006). A recent European study of naturalisation identifies nine factors associated with higher naturalisation rates. At the individual level, naturalisation is more likely for migrants who speak the destination country’s language, who have a parent born in the destination country and who reside longer within it. In addition, people who came from a poor or unstable country or from a former colony of the destination country are more likely to naturalize. Among the second generation (children of migrants), naturalisation seems to be less common among Muslims than among others. In the destination country, the study finds higher naturalisation rates where citizenship law is relatively permissive and where net migration rates are low (Dronkers and Vink 2010).

For migrants to the UK, the basis for initial entry also partially determines the likelihood of naturalising. Migrants who arrive in the UK with family visas or as skilled or highly-skilled workers (pre-PBS equivalents of Tier 1 and Tier 2 visas) are more likely to naturalise than those with student visas or temporary work visas. Students and temporary workers do not accumulate time toward fulfilling residency requirements unless they change their status to a category that is eligible for naturalisation, for instance through marriage to a British national or by obtaining a visa based on longer term work.

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Evidence gaps and limitations

Administrative data on naturalisations provide complete and presumably accurate counts of grants of citizenship by category of eligibility (residence, family, or registration). The Home Office compiles figures from a database in which caseworkers enter information about each applicant for naturalisation. Published statistics are generated from this database.

A minority of applications for citizenship are refused; these refusals are also tracked in administrative data, including the reason for rejection. Some of these simply fail to meet straightforward requirements such as length of residence; others reflect more discretionary judgements, such as the ‘good character’ requirement. In 2008, the Home Office changed its interpretation of the good character clause, making it difficult or impossible for people with past criminal convictions to attain citizenship.

Since naturalisation represents a change in relationship between an individual and the government, trends in naturalisation reflect not only trends in migration but also changes in government policy and administrative practice. Several cases are discussed in this briefing in which a change in policy or administrative practice had noticeable effects on the number of naturalising citizens in a given year or period. However, a crucial limitation is that administrative data on applications, grants and refusals cannot show the number of potential citizenship applications that might be deterred by added requirements. These include the 2004 and 2005 changes requiring a higher standard of English language proficiency and a demonstration of knowledge of life in the UK, and the fees accompanying applications for settlement, naturalisation, and the Life in the UK test. Some research attempts to estimate this deterrent effect (Ryan 2008), but this requires estimations based on assumptions and cannot be counted straightforwardly in the data. Still, given that some individuals may not feel capable of passing the required language and knowledge tests, and others may have difficulty affording the fees (particularly families, since fees apply to each individual), this deterrence could be an important impact of these policies.

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  • Bloemraad, Irene. "Becoming a Citizen in the United States and Canada: Structured Mobilization and Immigrant Political Incorporation.” Social Forces 85, no. 2 (2006): 667-695.
  • Dronkers, Jaap, and Maarten Vink. “Explaining Immigrant Citizenship Status: First and Second Generation Immigrants in Fifteen European States.” MPRA Paper No. 26198, Maastricht Research School of Economics of Technology and Organization (METEOR), Maastricht University, 2010. Accessed 9 November 2010.
  • Home Office. “British Citizenship Statistics, United Kingdom, 2009.” Statistical Bulletin, Home Office, London, 2010.
  • Janoski, Thomas. The Ironies of Citizenship: Naturalization and Integration in Industrialized Countries. Cambridge: Cambridge University Press, 2010.
  • Ryan, Bernard. “Integration Requirements: A New Model in Migration Law.” Journal of Immigration Asylum and Nationality Law 22, no. 4 (2008): 303-316.
  • Sawyer, Caroline. “EUDO Citizenship Observatory Country Report: United Kingdom.” Florence: European University Institute, 2009. Accessed 9 November 2010.

Further Readings

  • Brubaker, R. Citizenship and Nationhood in France and Germany. Cambridge, MA: Harvard University Press, 1992.
  • Yang, P. Q. "Explaining Immigrant Naturalization." International Migration Review 28, no. 3 (1994): 449-477.

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