50+ Popular Irish Last Names/Surnames And Their Celtic Meanings

50+ Popular Irish Last Names To Connect You To Your Inner Paddy

November 20, 2019 Updated October 7, 2021

popular irish last names
Wildgaze Films/BBC Films

Passed down from generation to generation, last names connect us to the family that came before us. Some of us may have ancestors from further afield to where we live now, and surnames are a great way to trace our origins.

Thanks to a long history of emigration, Irish last names have pretty much infiltrated the globe. You’ll likely recognize a common one when you see it (Conan O’Brien or the Kennedys, anyone?). But there are plenty more rooted in Ireland’s clan history that show just how much family is in a surname.

Read on to see our list of popular Irish last names, their Irish spellings, and their meanings. If your family surname is listed below, now’s a great time to get connected to your roots!

RELATED: First Names That Come From Last Names

Irish last names, Irish surnames, blonde says she's Irish
Team Coco/Giphy
  1. Murphy
    Irish spelling: Ó Murchadha
    Meaning: Descendent of Murchadh, a sea warrior.
  2. O’Brien
    Irish spelling: Ó Briain
    Meaning: Descendent of Brian Boru, the High King of Ireland.
  3. Kennedy
    Irish spelling: Ó Cinnéide
    Meaning: Descendent of Cennétig Mac Lorcáin, father of Brian Boru.
  4. O’Reilly
    Irish spelling: Ó Raghallaigh
    Meaning: Descendent of Raghallach, King of Connacht (Ireland’s western province).
  5. O’Neill
    Irish spelling: Ó Néill
    Meaning: Descendent of Niall Noigiallach, an Irish king.
  6. Smith/McGowan
    Irish spelling: Mac Gabhann
    Meaning: Son of the blacksmith.
  7. O’Rourke
    Irish spelling: Ó Ruairc
    Meaning: Descendent of Ruarc, King of Bréifne (an area including counties Leitrim and Connacht).
  8. Walsh
    Irish spelling: Breathnach
    Meaning: Welshman.
  9. Murray
    Irish spelling: Ó Muireadhaigh
    Meaning: Descendent of Muireadhaigh, a seaman.
  10. Collins
    Irish spelling: Ó Coileáin
    Meaning: Descendent of the young warrior/hound.
  11. Sheeran
    Irish spelling: Ó Síorán
    Meaning: Descendent of Sírín.
  12. O’Sullivan
    Irish spelling: Ó Súilleabháin
    Meaning: Descendent of the dark-eyed.
  13. McCarthy
    Irish spelling: Mac Carthaigh
    Meaning: Son of Cárthach, King of Munster (Ireland’s southern province).
  14. Lynch
    Irish spelling: Ó Loinsigh
    Meaning: Descendent of Loingseach, a seaman.
  15. Fitzpatrick
    Irish spelling: Mac Giolla Phádraig
    Meaning: Follower of Saint Patrick.
  16. Sweeney
    Irish spelling: Mac Suibhne
    Meaning: Son of Suibhne, a Scottish lord whose grandson arrived to Ireland and brought the name with him.
  17. Regan
    Irish spelling: Ó Riagáin
    Meaning: Descendent of Riagáin. There were actually two Ó Riagáin clans in Ireland, one related to Brian Boru and one that powerfully ruled in the county of Meath.
  18. O’Leary
    Irish spelling: Ó Laoghaire
    Meaning: Descendent of Laoghaire, a calf-keeper.
  19. Mullan/Mullen/Mullins
    Irish spelling: Ó Maoláin
    Meaning: Descendent of Maelan, King of Maigh Seóla (in Galway).
  20. Mulligan
    Irish spelling: Ó Maolagain
    Meaning: Descendent of the bald man.

    Irish last names, Irish surnames, cartoon elderly couple rubbing each other's bald heads
  21. Ryan
    Irish spelling: Ó Riain
    Meaning: Descendent of Riain, a king.
  22. Quinn
    Irish spelling: Ó Cuinn
    Meaning: Descendent of Conn, a wise chief.
  23. Kelly
    Irish spelling: Ó Ceallaigh
    Meaning: Descendent of Ceallach, meaning war or contention.
  24. Whelan
    Irish spelling: Ó Faoláin
    Meaning: Of the wolf.
  25. Maher
    Irish spelling: Ó Meachair/Meagher
    Meaning: Of the generous/hospitable.
  26. Hogan
    Irish spelling: Ó hÓgáin
    Meaning: Of youth.
  27. O’Keeffe
    Irish spelling: Ó Caoimh
    Meaning: Of the noble/the gentle.
  28. O’Dwyer
    Irish spelling: Ó Dubhuir
    Meaning: Black.
  29. Buckley
    Irish spelling: Ó Buachalla
    Meaning: Descendent of the cow herder.
  30. McDermott
    Irish spelling: Mac Diarmada
    Meaning: Son of Diarmait, King of Leinster and High King of Ireland.
  31. O’Connor
    Irish spelling: Ó Conchobhair
    Meaning: Descendent of Conchubhair Donn, another King of Connacht.
  32. Dunne
    Irish spelling: Ó Duinn
    Meaning: Brown.
  33. Donovan
    Irish spelling: Ó Donnabháin
    Meaning: Brown-black.
  34. Lyons/Lyne
    Irish spelling: Ó Laighin
    Meaning: Of the spear.
  35. Donnelly
    Irish spelling: Ó Donnghaile
    Meaning: Brown valor.
  36. McMahon
    Irish spelling: Mac Mathúna
    Meaning: Son of Mathghamhna, Chief of a clan in Aran.
  37. Casey
    Irish spelling: Ó Cathasaigh
    Meaning: Alert, vigilant and watchful.
  38. Kenny
    Irish spelling: Ó Cionaoith
    Meaning: Fire born.
  39. Foley
    Irish spelling: Ó Foghladh
    Meaning: Plunderer.
  40. Cleary/Clarke
    Irish spelling: Ó Cléirigh
    Meaning: Descendent of the clerk/cleric.
  41. Duffy
    Irish spelling: Ó Dufaigh/Ó Dubhthaigh
    Meaning: Black.
  42. Moore
    Irish spelling: Ó Mordha, Muir, Moir
    Meaning: Moir/Ó Mordha could mean of greatness or grandiose while Muir means sea.
  43. Brennan
    Irish spelling: Ó Braonáin/Ó Branáin
    Meaning: Ó Braonáin means of the droplet while Ó Branáin means of the raven.
  44. Doyle
    Irish spelling: Ó Dubhghaile
    Meaning: Descendent of Dubhghal, meaning black valor.
  45. Gallagher
    Irish spelling: Ó Gallchobhair
    Meaning: Descendent of Gallchobhar, an Irish king.
  46. McLoughlin
    Irish spelling: Mac Lochlainn
    Meaning: Son of the vikings.
  47. Daly
    Irish spelling: Ó Dálaigh
    Meaning: Of the assembly.
  48. Boyle
    Irish spelling: Ó Baoill
    Meaning: Vain pledge.
  49. O’Shea
    Irish spelling: Ó Séaghdha
    Meaning: Descendent of the majestic.
  50. Farrell
    Irish spelling: Ó Ferghail
    Meaning: Man of valor.

    Irish surnames, Irish last names, man licking lips
  51. Barry
    Irish spelling: O’ Baire
    Meaning: Fair-headed, fair-haired, pointed, spear, or sharp.
  52. Campbell
    Irish spelling: Caimbeul
    Meaning: Crooked mouth.