Naturalisation is the process by which British citizenship is conferred upon a foreign national after he or she fulfils the requirements established by the immigration and nationality laws of the United Kingdom.

Normally, a foreign national must have fulfilled the six-year residency requirement before she or he can be granted citizenship. However, spouses of British citizens are entitled to apply to be naturalised after residing in the UK for three years. The general eligibility requirements are based around the character, residential circumstances and immigration restrictions of the applicant. It should be noted that a number of checks and tests are carried out for the purposes of gaining naturalisation and subsequent time needs to be allowed for these to be completed. The processing times for naturalisation applications vary, but are generally within around six to eight months.

In order to become naturalised, the applicant must be aged eighteen or over; of sound mind; have sufficient understanding of UK life and language; of good character, and married to and living in a valid marital union with the same UK citizen spouse for all three years.

The residential criteria, also known as the residential qualifying period, for those spouses of British citizens that want to apply for UK naturalisation include being a legal resident in the UK for a minimum of three years. This entails obtaining further leave to remain (FLR) subsequent to arrival in the UK on a settlement-class fiancee visa, and indefinite leave to remain (ILR) upon completion of a two-year probationary period in the UK as the spouse of a British citizen. Those who wish to apply for naturalisation on these grounds must not have spent more that 270 days in the last three years of residency outside of the UK, and during the last 12 months the applicant must not have been outside of the UK for more than 90 days.

Immigration requirements that need to be met for your naturalisation application as the spouse of a British citizen include being free from immigration time restrictions on the day of your application and to have committed no breaches of the immigration rules during your entire residential qualifying period in the UK. Being free from any time restrictions means having been legally accorded the privilege of residing permanently in the United Kingdom as an indefinite leave to remain (ILR) holder in accordance with the immigration laws.

There is a further requirement related to residency in the UK that is a common cause of applications being rejected. It is imperative that applicants are physically present in the UK at the time of the application for naturalisation, with no exceptions, including those relating to detention, the armed forces or diplomatic immunity, with these counting as time outside of the UK. The only other category in which you can apply for naturalisation as the spouse of a British citizen relates to the crown and designated service, which only acts as the alternative to the residential criteria and all other requirements must still be met. The crown and designated service refers to the particular working situation of your British husband or wife.

Important Announcement: New UK Immigration Rules after 9 July 2012