British Citizenship by Descent: Eligibility Rules


British citizenship by descent allows individuals who were not born in the UK to become British citizens on the basis of a parent’s, or in some cases grandparent’s, British status.

What is British citizenship by decent?

Under UK nationality rules, British citizens are classed as either having British citizenship by descent’ or ‘British citizenship otherwise than by descent’.

Citizens otherwise than by descent can normally pass on British citizenship through one generation to children born abroad, although the child will be unable to transmit their citizenship to subsequent generations overseas. This can be attained through birth, registration, naturalisation or adoption.

With British citizenship by descent, however, you can not normally pass citizenship to children born outside of the UK, unless they were born to a parent in crown, designated or EU service.

No other of the rights or duties that go with British citizenship are affected by this status.

British citizen by descent applies where an individual is born outside the UK and one or both parents are British citizens.

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Eligibility for British citizenship

Section 14(1) of the British Nationality Act 1981 provides an extensive definition of the term ‘British citizen by descent’.

You will automatically acquire British citizenship by descent if you were born outside the UK on or after 1 January 1983 and one or both your parents are British citizens otherwise than by descent.

There are, however, several other ways in which you may be deemed a British citizen by descent, in particular, by registration.

For example, if you were born before 1 January 1983 to a British mother you can apply for registration as a British citizen under section 4C of the British Nationality Act 1981, but you will be regarded as a British citizen by descent rather than otherwise by descent.

Where a British citizen falls outside of the definition provided for by virtue of section 14(1) of the 1981 Act for British citizens by descent, they will automatically be a British citizen otherwise than by descent.

You can be a British citizen otherwise than by descent in the following circumstances:

  • Where you were born or adopted in the UK before 1 January 1983
  • Where you were born in the UK on or after 1 January 1983 to a mother or, if your parents were married, a father, who was a British citizen or settled in the UK
  • Where you were born in the UK on or after 1 July 2006 where either parent is a British citizen or settled in the UK
  • Where you have been given citizenship after applying for it in your own right, for example, by being naturalised or registered as a British citizen.

There are also some limited circumstances in which a child who is born outside the UK to a British citizen otherwise than by descent may also be a British citizen otherwise than by descent.


A child born outside the UK will not usually be a British citizen if neither parent is a British citizen otherwise than by descent since a parent who is a British citizen by descent cannot normally pass that status on.

However, an exception may be allowed where the parent was in one of three types of service as set out below. Different rules apply to children born to a parent who, at the time of birth, is a British citizen in:

  • Crown service
  • Specially designated service
  • European Community institution service.

A child will be a British citizen otherwise than by descent at birth if, when the child is born, one of the parents:

  • Is a British citizen, and
  • Is working outside the UK in one of the three types of service mentioned above, and
  • Was recruited to that service in the UK, or if the child was born on or after 21 May 2002, in a qualifying territory, or
  • If serving with a European Community institution, was recruited in a country that was a member of the European Union at the time.

Automatic acquisition

The automatic acquisition of British citizenship refers to where you acquire citizenship without the need to register your right. Where a child is born overseas to a parent who is a British citizen otherwise than by descent, that child will automatically acquire British citizenship.

That said, regardless of whether you are automatically a British citizen, or whether you are required to register your right to citizenship, this will entitle you to apply for either a child’s passport if you’re aged under 16 or an adult passport if you’re aged over 16.

What is citizenship by double descent?

In some cases, British Citizenship by ‘double descent’ may be attainable where at least one of your grandparents was British or born in the UK.

British Citizenship by descent (grandparent) applications will be considered on discretionary grounds, and it will be for the applicant to provide sufficient evidence to support their claim.

Specific scenarios for children under 18 for example may apply and provide eligibility for double descent, but will not be available once the child turns 18 and becomes subject to adult nationality rules.

This is a complex area of nationality law and will turn on the facts. Taking professional legal advice will ensure you are considering all of your options and electing for the most appropriate for the circumstances.

How do I prove British citizenship by descent or otherwise?

If you do not wish to apply for a British passport, but require confirmation of how you acquired British nationality for another purpose, you can apply for a certificate of entitlement using Form ROA. This will prove your right of abode in the UK as a British citizen, ie; your right to live and work in the UK restriction free.

Alternatively you can ask the Home Office for a letter of status using Form NS. When submitting your application you must supply documentary evidence of the identity of those people; ie; your ancestors, you use to support your claim to British citizenship.

This evidence can include evidence of marriage and registration as citizens of the UK and Colonies or British citizenship, including immigration status, where this is relevant.

By way of example, you may need to provide a birth certificate showing your parents’ details and the country in which they were born or a certificate of naturalisation or registration issued describing the holder as a British citizen. You may, alternatively, need to produce evidence from the Home Office of settled status and that one or both your parents had indefinite leave to remain in the UK.

Please note, however, that a status letter issued by the Home Office is not a certificate of nationality. This letter merely records UKVI’s opinion that a person possesses a form of British nationality. Only the courts can determine conclusively whether that person is actually a British national.

As such, if a person wishes to establish whether they hold British nationality they should be advised to make a passport application or an application for a certificate of entitlement to the right of abode.


Founder and Managing Director Anne Morris is a fully qualified solicitor and trusted adviser to large corporates through to SMEs, providing strategic immigration and global mobility advice to support employers with UK operations to meet their workforce needs through corporate immigration.

She is a recognised by Legal 500and Chambers as a legal expert and delivers Board-level advice on business migration and compliance risk management as well as overseeing the firm’s development of new client propositions and delivery of cost and time efficient processing of applications.

Anne is an active public speaker, immigration commentator, and immigration policy contributor and regularly hosts training sessions for employers and HR professionals

About DavidsonMorris

As employer solutions lawyers, DavidsonMorris offers a complete and cost-effective capability to meet employers’ needs across UK immigration and employment law, HR and global mobility.

Led by Anne Morris, one of the UK’s preeminent immigration lawyers, and with rankings in The Legal 500 and Chambers & Partners, we’re a multi-disciplinary team helping organisations to meet their people objectives, while reducing legal risk and nurturing workforce relations.

Legal Disclaimer

The matters contained in this article are intended to be for general information purposes only. This article does not constitute legal advice, nor is it a complete or authoritative statement of the law, and should not be treated as such. Whilst every effort is made to ensure that the information is correct at the time of writing, no warranty, express or implied, is given as to its accuracy and no liability is accepted for any error or omission. Before acting on any of the information contained herein, expert legal advice should be sought.

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