How does Citizenship by Descent (Foreign Births Register) work in Ireland, and who qualifies?

Irish citizenship by descent is generous and well known. If you have an Irish-born parent, you are generally an Irish citizen automatically. If your link is an Irish-born grandparent, you can become a citizen by registering in the Foreign Births Register, which is administered by the Department of Foreign Affairs. Crucially, no residence in Ireland is required for this route.

The documentation is where care is needed. You will need civil-status documents — birth and marriage certificates — for each generation in the line. For more distant ancestry, an intervening parent must have registered in the Foreign Births Register before the applicant's birth, so the timing of registrations across generations matters.

Because an unbroken, well-documented line is essential and the rules have specific timing conditions, it is worth confirming the requirements on irishimmigration.ie and the Department of Foreign Affairs site before assuming eligibility. ACME can help you trace and assemble the certificates needed and check that your line qualifies.