Irish citizenship through a grandparent: the Foreign Births Register
If a grandparent was born anywhere on the island of Ireland, you may be able to become an Irish citizen without living there. Who can apply, the documents you need, what it costs and how long it takes.
If one of your grandparents was born anywhere on the island of Ireland, you may be able to become an Irish citizen through the Foreign Births Register. There is no language test and no need to live in Ireland. Ireland allows dual citizenship, so you can keep your current passport. An Irish passport also makes you an EU citizen, which opens the door to living in any EU country. It may be the simplest first step toward a move to Europe.
Who can apply
You may be able to register if one of these applies to you:
- A grandparent was born on the island of Ireland. That includes Northern Ireland as well as the Republic.
- A parent was an Irish citizen when you were born, but was not born in Ireland. For example, your parent may have become Irish through the Foreign Births Register or by naturalisation.
Great-grandparents. A great-grandparent link works only in one case: your parent was entered on the Register before you were born. If your parent registers after your birth, you cannot claim through them. Children born after a parent registers can be registered in turn.
Spouses. A spouse does not gain any right through your registration. Each person applies on their own line of descent.
Check your exact family line with the official source before you start, because eligibility turns on details like dates of birth and registration.
The documents you will need
The work in an application is mostly gathering paperwork. Expect to collect:
- civil, long-form birth certificates for you, your Irish-link parent and your Irish-born grandparent
- marriage certificates for those generations
- death certificates where they apply
- certified copies of identity documents, witnessed by an approved witness
- proof of your address, and photos
Long-form birth certificates show parents’ names, which is how the chain of descent is proven. Start ordering these early. Records from Ireland, the US, Canada and the UK can each take time to arrive.
How to apply
- Confirm your line. Work out which grandparent was born in Ireland and which parent connects you to them.
- Gather the certificates. Collect every document for all three generations before you apply.
- Apply online. You apply online with Ireland’s Department of Foreign Affairs, from anywhere in the world.
- Post your documents. After the online step, you post your supporting documents to the Foreign Birth Registration unit.
- Wait for registration. When your entry is made, you become an Irish citizen from that date. You can then apply for an Irish passport.
Citizenship starts from the date of registration, not from your birth. That matters for your children. Only children born after you register can claim through you as the child of an Irish citizen.
What it costs and how long it takes
A 2024 answer in the Irish parliament gave the fee as EUR 278 for an adult and EUR 153 for someone under 18, each including EUR 8 postage. We could not confirm the 2026 fee on an official page, so check the current figure before you pay.
The same 2024 answer described a normal turnaround of 8 to 9 months. Secondary sources in 2025 and 2026 report about 9 to 12 months from receipt of a complete application. Missing or inconsistent documents slow things down, so check every name and date before you send.
Certificates, certified copies and postage add to the cost. These vary by country and office.
What Irish citizenship gives you
Once you are registered, you may:
- Live and work in Ireland with no visa or permit. Compare that with the salary thresholds for Irish work permits, which start at EUR 40,904 for Critical Skills jobs.
- Live in other EU countries. EU citizens can move to any other EU country to work, study, look for a job or retire.
- Live and work in the UK. Irish citizens have free movement with the UK under the Common Travel Area.
- Pass citizenship on. Children born after your registration can be registered too.
Registration does not change your tax position. Irish citizenship does not make you an Irish tax resident. US citizens stay taxable by the US on worldwide income wherever they live. Speak to a tax adviser before you move.
What catches people out
- The grandparent must be Irish-born. A grandparent who was Irish by descent but born elsewhere does not qualify you through this route. The great-grandparent rule above may still help if your parent registered in time.
- Order matters for families. If you plan to register a child, register yourself first, and know that only children born afterwards can claim through you.
- Name and date mismatches. If a name is spelled differently or a date differs between certificates, gather supporting records that tie them together before you apply.
For the wider picture of living in Ireland, read our guide to moving to Ireland, or see the Foreign Births Register entry in our routes table.
This is general information, not legal or immigration advice. Confirm your eligibility and the current fee with Ireland’s Department of Foreign Affairs before you apply.