Since your parent was born on the island of Ireland (including Northern Ireland), you are automatically considered an Irish citizen.
You can apply directly for an Irish passport without needing to register as a foreign birth.
Provided to you when you apply on the official website
Must include parent(s) names
Only if using a married name
Official government correspondence, utility bills, or bank statements
Similar to proof of address (must be a separate document)
Government-issued ID or certified copy of driver's license
Important Note
Proof of name and address must be separate documents. You cannot use the same document for both requirements.
Your parent's original birth certificate from Ireland
If their name has changed (marriage, divorce, etc.), provide documents linking their identity to your birth certificate
Don't worry – you don't need the actual certificate from decades ago! An "original" document simply means a certified copy ordered directly from the official government registrars.
These newly issued certificates are legally equivalent to the historical documents and are fully accepted for citizenship applications.