If either of your parents was an Irish citizen who was born in Ireland, then you are automatically an Irish citizen, irrespective of your place of birth. If you are an Irish citizen, you can apply for an Irish passport. You do not need an Irish passport in order to be an Irish citizen but having an Irish passport is evidence that you are an Irish citizen.
If you were born outside Ireland to an Irish citizen who was born outside Ireland, then you are entitled to become an Irish citizen.
If your parent derived Irish citizenship in another manner, for example, through marriage, adoption or naturalisation, and was an Irish citizen at the time of your birth, you can become an Irish citizen.
If the parent through whom you derive Irish citizenship was deceased at the time of your birth, but would have been an Irish citizen if alive at that time, you are also an Irish citizen. Also, you derive citizenship through an Irish parent whether or not your parents were married to each other at the time of your birth.
Claiming Irish citizenship: Before you can claim Irish citizenship, you must have your birth registered in the Foreign Births Register – see below. If you are entitled to register, your Irish citizenship is effective from the date of registration – not from the date when you were born.
If one of your grandparents is an Irish citizen who was born in Ireland, but neither of your parents was born in Ireland, you may become an Irish citizen. You will need to have your birth registered in the Foreign Births Register – see below.
Unless at least one parent or an Irish-born grandparent was an Irish citizen at the time of your birth, you cannot claim Irish citizenship on the basis of extended previous ancestry (that is, ancestors other than your parents or grandparents). In addition, you cannot claim Irish citizenship on the basis that a relation such as a cousin, aunt or uncle was an Irish citizen if none of your parents or grandparents was an Irish citizen at the time of your birth.
| If you are: | Then you are: | |
| A | Born in the island of Ireland on or before 31 December 2004 | Entitled to Irish citizenship or you are an Irish citizen |
| B | Born on the island of Ireland on or after 1 January 2005 |
Entitled to Irish citizenship if one or both of your parents:
|
| C | Child of A, born outside the island of Ireland | An Irish citizen |
| D | Child of C and a grandchild of A, born outside the island of Ireland | Entitled to Irish citizenship, but you must first register in the Foreign Births Register |
| E | a child of D and a great-grandchild of A, born outside the island of Ireland | Entitled to Irish citizenship, by having your birth registered in the Foreign Births Register, but only if your parent D had registered by the time of your birth. |