New British Citizenship Process for Irish Citizens

Legally reviewed by: Sherena Lawrence Aug 2025 In: Immigration

Simpler British Citizenship Route for Irish Citizens Now Open

On 22 July 2025, the British Nationality (Irish Citizens) Act 2024 officially came into force, following the enactment of the Commencement Regulations 2025 on 1 July 2025 .

The Act introduces a simpler route for Irish citizens who have been resident in the UK for five years to register as British under section 4AA of the British Nationality Act 1981.

Key Features of the New Section 4AA Registration Route

• Residency requirement: An applicant must have been physically present in the UK at the start of a continuous five‑year period ending on the date of application.
• Absence limits: No more than 450 days of absence during the five years, and no more than 90 days in the final 12 months.
• Compliance with immigration laws: The applicant must not have been in breach of UK immigration laws at any point in the five‑year period.
• Good character requirement: Applicants must meet the same good character standard as other routes to citizenship.
• Discretion for exceptional cases: The Secretary of State may exercise discretion in special circumstances to accept applications that do not strictly meet the above criteria.
• “Otherwise than by descent” status: Those registered under this route acquire British citizenship otherwise than by descent, enabling them to pass citizenship to children born abroad.

When Can Applications Be Made and What Is the Cost?

The simplified registration route became available to both adults and children on 22 July 2025. Most applicants will be able to submit their application online using Form B (OTA). However, applicants who are resident in the Channel Islands, the Isle of Man, or a British Overseas Territory must instead complete a paper form.

To assist applicants, the Home Office has published Guide B3: Registration as a British citizen – Irish citizens, which outlines the eligibility requirements and application process. It has also issued dedicated caseworker guidance titled Acquisition of British citizenship: Irish citizens, which provides more insight into how applications will be assessed.

The application fee has been set at £723 for adults and £607 for children. While still a significant cost, these fees are significantly lower than the current £1,605 charged for a standard naturalisation application.

Importantly, a fee waiver is available in certain circumstances. This applies where:

• A child is looked after by a local authority; or
• The applicant’s family can demonstrate that they are unable to afford the fee.

Migration and Citizenship Minister Seema Malhotra confirmed these provisions when the route launched, helping to ensure that children in care or from low-income families are not excluded from applying due to the cost.

Why This Matters

Irish citizens have long held a unique status in the UK under the Common Travel Area, including rights to live, work, access services, and vote. Yet the path to British citizenship remained complex, involving naturalisation, language tests, and formalities. This reform recognises the historical and legal ties between the two nations and offers a fairer, more straightforward route for Irish citizens to become British.

Irish Citizens in the UK

Irish citizens already enjoy a high level of security in the UK through their unique status under the Common Travel Area. They are treated as settled from the point at which they become ordinarily resident. This means that there is no requirement to apply under the EU Settlement Scheme. However, some choose to do so.

The introduction of this simplified route to British citizenship, alongside significantly lower application fees, is a welcome change. Therefore, we expect that many eligible Irish citizens will take advantage of this opportunity to formalise their status and secure the benefits of citizenship.

How Our Immigration Solicitors Can Help

At Cartwright King Solicitors, our immigration team can help you checking your eligibility, prepare and submit your application, to make sure all your documents are in order. For help with your UK immigration matter, get in touch with our specialist solicitors today.