Guidance

Form B(OS): guidance

Guidance to register as a British citizen if you have certain other types of British nationality.

• From: UK Visas and Immigration
• Published: 22 March 2019
• Last updated: 3 August 2026
  Show all updates

  1. 3 August 2026

     Updated the contact information.

  2. 7 July 2026

     Updated the application processing times section with information about the priority service.

  3. 23 April 2026

     Updated the section on travelling to and from the UK after registering to include information for British citizens who may also hold rights under the EU Withdrawal Agreement.

  4. 6 March 2026

     Updated the 'Travelling to and from the UK after registering' section.

  5. 22 April 2025

     Updated information about biometric enrolment, citizenship ceremonies and citizenship-related queries and added a new section about digital status.

  6. 24 July 2024

     Added a section on application processing times, and added more details to the section on travelling to and from the UK after registering.

  7. 4 October 2023

     Document format and style updated. Outdated information removed or updated accordingly. References and links to fees updated.

  8. 22 February 2022

     Accessible HTML version added.

  9. 22 March 2019

     First published.

Documents

Form B(OS): guidance (accessible)

HTML

Form B(OS): guidance

PDF, 220 KB, 17 pages

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Details

Read the B(OS) guidance to find out if you can register as a British citizen if you are a British Overseas citizen, British subject, British protected person, or British National (Overseas) and have no other citizenship or nationality.