Share This:

Although Ireland is a relatively small country, there are many differences between each and every county – and surnames are no exception. Here are the most popular last names for every county of Ireland.

The most popular last names for every county of Ireland

Having evolved over the centuries to be the surnames we recognise today, Irish last names have a rich and vibrant history. In early times, when Ireland had a much smaller population and mass movement of people was uncommon, it was not unusual for people to be known by only one name. However, as the population began to grow in the Middle Ages, the Gaelic Clann system was established in Ireland to give people a shared identity with their people of the tribe and the area from which they came.

While many Irish surnames have evolved from Gaelic to English over hundreds of years, many traditional Irish names remain common across Ireland today. So, here are the most popular last names for every county of Ireland.

1. Antrim – Smith

Image removed.

Smith is not just Antrim’s most popular name, but it is also the most common name in Europe.

The name derives from the Old English smið or smiþ, meaning “one who works in metal”, thus indicating that the owner of this surname would have been a metal worker or blacksmith.

Do you have ancestors from County Antrim? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

2. Armagh – Campbell

Image removed.

The most popular surname in Armagh is Campbell, which is derived from the Gaelic terms “cam” and “beul”, meaning “crooked mouth” or “wry mouthed”.

Do you have ancestors from County Armagh? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

3. Carlow – Mullins

Image removed.

An anglicised form of the Irish O’Maolain, the popular Carlow surname Mullins is thought to be derived from “maol” meaning “bald”.

Do you have ancestors from County Carlow? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

4. Cavan – Brady

Image removed.

The Irish surname Brady is derived from the Gaelic surname Ó Brádaigh or Mac Brádaigh and means “spirited and broad”.

Do you have ancestors from County Cavan? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

5. Clare – MacMahon

Image removed.

MacMahon, from the Old Irish Mac Mathghamhna, means “son of the bear” or “son of the bear-calf”.

Do you have ancestors from County Clare? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

6. Cork – O’Connor

Image removed.

One of the most popular last names for every county of Ireland, O’Connor, derives from the Gaelic Ó Conchobhair, meaning “grandson/descendant of Conchobar”.

The Irish given name Conchobhair means “lover of hounds”.

Do you have ancestors from County Cork? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

7. Derry – Bradley

Image removed.

An English surname meaning “broad wood” or “broad meadow” in Old English, Bradley is also an anglicisation of the Gaelic Ó Brolacháin from County Tyrone.

Do you have ancestors from County Derry? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

8. Donegal – Gallagher

Image removed.

Gallagher has been a popular family name in Donegal since as far back as the 10th-century when the Gallagher (or Gallchobhair mac Rorcan) family ruled the Tir Chonaill county.

Do you have ancestors from County Donegal? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

9. Down – Thompson

Image removed.

The surname Thompson is not only popular in Ireland but also across England, Scotland, and Wales.

A patronymic surname of Scottish origin, Thompson means “son of Thomas”.

Do you have ancestors from County Down? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

10. Dublin – Byrne

Image removed.

In the Irish language, Byrne translates as Ó Broin and means “descendant of Bran”.

The name has been traced back as far as the ancient Celtic chieftain, Bran mac Máelmórda, King of Leinster, who was deposed in 1018.

Do you have ancestors from County Dublin? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

11. Fermanagh – Maguire

Image removed.

The Irish surname Maguire comes from the Gaelic Mac Uidhir, meaning “son of the dun or dark coloured one”.

Do you have ancestors from County Fermanagh? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

12. Galway – Kelly

Image removed.

The popular Galway surname Kelly comes from the Gaelic O’Ceallaigh, which means “bright headed” or “troublesome”.

Do you have ancestors from County Galway? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

13. Kerry – O’Sullivan

Image removed.

The surname O’Sullivan derives from the Sullivan clan, an Irish Gaelic clan based in what is today County Cork and County Kerry.

Do you have ancestors from County Kerry? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

It is interpreted as “little dark-eyed one”.

14. Kildare – O’Toole

Image removed.

The O’Tooles were historically one of the most powerful families in Leinster, and the translation of the Irish name means “descendant of the mighty people”.

Do you have ancestors from County Kildare? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

15. Kilkenny – Brennan

Image removed.

The most popular Irish surname in Kilkenny, Brennan, is an anglicised form of three different Irish surnames: Ó Braonáin, Mac Branáin and Ó Branáin.

This patronymic surname means “son of Branán”, a personal name meaning “little raven”.

Do you have ancestors from County Kilkenny? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

16. Laois – Dunne

Image removed.

Dunne is one of the most popular last names for every county of Ireland.

This Irish surname is derived from the Irish Ó Duinn and Ó Doinn, meaning “dark” or “brown.”

Do you have ancestors from County Laois? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

17. Leitrim – Reynolds

Image removed.

In Gaelic, the name Reynolds is Mac Raghnaill, which comes from the Old Norse name Rognvald.

The patronymic surname meaning “son of Reynold” derives from the given name meaning “powerful ruler”.

Do you have ancestors from County Leitrim? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

18. Limerick – Ryan

Image removed.

In some cases, Ryan is a shortened form of the patronymic name O’Ryan, an anglicised form of the Gaelic surname Ó Riain.

In Irish, Ryan is thought to mean “king”, “water”, or “ocean”, and is today among the top ten most common surnames in Ireland.

Do you have ancestors from County Limerick? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

19. Longford – O’Reilly

Image removed.

O’Reilly is a name of Gaelic origin deriving from the kings of East Bréifne in what is today County Cavan.

O’Reilly is the patronymic form of the Irish name Reilly, which means “extroverted one”.

Do you have ancestors from County Longford? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

20. Louth – Matthews

Image removed.

Matthew is a variant of the Gaelic name MacMahon, meaning “son of Matthew”.

Do you have ancestors from County Louth? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

21. Mayo – Walsh

Image removed.

Walsh is an Irish surname that means “Briton”, “foreigner”, or literally “Welshman”.

It is a name that was brought to Ireland by Welsh, Cornish, and Cumbrian soldiers during and after the Norman invasion of Ireland.

Do you have ancestors from County Mayo? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

22. Meath – O’Farrell

Image removed.

O’Farrell is the most common Irish last name in County Meath. It derives from the Gaelic O’Fearghail, which means “man of valour”.

Do you have ancestors from County Meath? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

23. Monaghan – Connolly

Image removed.

Connolly is the anglicised form of the Old Gaelic O’Conghaile, which means “fierce as a hound or wolf”.

Do you have ancestors from County Monaghan? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

24. Offaly – Hennessy

Image removed.

Hennessy is the anglicised form of the Gaelic name Ó hAonghusa, which came from the Irish Kingdom of Uí Failghe or modern-day County Offally.

Do you have ancestors from County Offaly? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

25. Roscommon – McDermott

Image removed.

McDermott derives from the Gaelic Mac Diarmada, which means “son of Diarmuid” or “free man”.

This Irish name comes from Tadhg mac Diarmata, who was King of Connacht before the Norman invasion.

Do you have ancestors from County Roscommon? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

26. Sligo – McGinn

Image removed.

The anglicised form of the Gaelic Mag Finn, McGinn means “son of Fionn”.

Variations of the name include McGinne, Ginn, McGing, Ging, McKing, and Maginn.

Do you have ancestors from County Sligo? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

27. Tipperary – Purcell

Image removed.

Purcell is an Irish name of French or Norman origin, which was given to those whose occupation was tending to pigs.

Do you have ancestors from County Tipperary? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

28. Tyrone – O’Neill

Image removed.

One of the most popular last names for every county of Ireland is O’Neill.

An anglicisation of the Gaelic Ua Néill, meaning “son of Niall”, an Irish name that means champion.

Do you have ancestors from County Tyrone? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

29. Waterford – Power

Image removed.

The Irish surname Power actually derives from Norman or French origin as it was brought to Ireland during the Anglo-Norman invasion of the late 12th-century.

From the French word, povre, Power means poor or pauper.

Do you have ancestors from County Waterford? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

30. Westmeath – Lynch

Image removed.

The most popular surname in Westmeath, Lynch, derives from the Gaelic Ó Loingsigh, meaning “son of Loingseach”.

The given name Loingseach means “having or belonging to a fleet of ships”, thus indicating that the owner of this name would have been a mariner or seaman.

Do you have ancestors from County Westmeath? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

31. Wexford – Murphy

Image removed.

One of the most well-known Irish surnames, Murphy, is the most popular last name in Wexford.

The Gaelic equivalent of this anglicised surname is Ó Murchadha, and it means “sea battler”.

Do you have ancestors from County Wexford? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.

32. Wicklow – Cullen

Image removed.

The surname Cullen is of Gaelic origin, and it is believed to be derived from the pre-8th-century Old Gaelic name O’ Cuileannain or Ó Cuilinn, meaning “son of Cuilleannain”.

Do your Irish ancestors have any of the surnames listed above? Add their profile to the IrelandXO Ancestor Chronicles and help other descendants from the same family discover more about their Irish ancestry and the place in Ireland where they come from.

Do you have ancestors from County Wicklow? Add them to IrelandXO today and connect with other people descended from the same place.

Image removed.


Read More

 

We hope you have found the information we have shared helpful. While you are here, we have a small favour to ask. Ireland Reaching Out is a non-profit organisation that relies on public funding and donations to ensure a completely free family history advisory service to anyone of Irish heritage who needs help connecting with their Irish place of origin. If you would like to support our mission, please click on the donate button and make a contribution. Any amount, big or small, is appreciated and makes a difference. 

Donate Now