O'Halloran
surname · Latin script
Meaning: Descendant of Halloran
(measured from records)Officially recorded in 6 countries · latest register: Surnames of England and Wales (taliesin-arlein.net, Sept 2002 electoral register), 2002
/oʊˈhæɫɝən/(machine-generated) pronunciation, model-generated
O'Halloran is a surname written in the Latin script, with more bearers in the United States than in any other country.
- IEIreland≈1 in 14K(inferred from the name graph)
- AUAustralia≈1 in 17K
- GBUnited Kingdom≈1 in 73K
carrying the name, as counted by its national register where one exists and as Mondonomo estimates it elsewhere (marked ≈ and "est." on hover). Where a country counts another spelling of the name rather than O'Halloran itself, the figure is that spelling’s, and it is named. One hue, darker where it is more common; hover a country for its figure.
- United States (measured from records)
- Record sources
- 242 (measured from records)
- ≈1 in 14K (inferred from the name graph)
5,465 named Halloran, 2010
corpus datasets behind its best-documented spelling
strongest: highest-authority source
Ireland, est.
measured from records inferred from the name graph
Spellings & scripts
(measured from records)One other spelling is counted as the same name:
Locally spelled Ohalloran in US United States, GB United Kingdom, CA Canada and 4 more.
Spellings marked ● are how people bearing the name write it in our records, and ○ marks a model's transliteration; click a spelling to open its page.
Meaning & origin
(measured from records)Descendant of Halloran.
Cited for this meaning 1
- Encyclopedia of surnames [the complete companion to tracing your names history]
Attested in 1 language in the etymology graph.
Where in the world
(measured from records)O'Halloran counted together with the spellings and other-language forms grouped with it. Where a register counted another spelling, the row names it.
Sorted by bearers: national registers' counts, and Mondonomo's estimates (≈, est.) where no register counts.
| Country | Most common spelling | Sources | ||||
|---|---|---|---|---|---|---|
| US United States | — | 5,465as Halloran | 1 in 61K | 5.5K | Ohalloran | 242 |
| AU Australia | — | ≈1,500 est. | ≈1 in 17K | — | O'Halloran | 112 |
| GB United Kingdom | — | ≈900 est. | ≈1 in 73K | 2.2K | Ohalloran | 117 |
| EG Egypt | — | ≈510 est. | ≈1 in 205K | — | Ohalloran | 2 |
| CA Canada | — | ≈490 est. | ≈1 in 77K | — | Ohalloran | 81 |
| IE Ireland | #444 | ≈360 est. | ≈1 in 14K | — | O'Halloran | 73 |
| JM Jamaica | — | ≈58 est. | ≈1 in 48K | — | Ohalloran | 1 |
| ES Spain | — | 13 | 1 in 3.8M | 42 | Ohalloran | 12 |
| IS Iceland | — | ≈13 est. | ≈1 in 28K | — | Ohalloran | 1 |
5,465 people counted by Census Bureau — Surname Frequency 2010, 2010, counting the spelling halloran. Exact figures are national registers' own counts, while figures marked ≈ and est. are Mondonomo’s estimates, counted from our sources and calibrated against those registers; hover one for how far to trust it in that country. A dash means neither exists.
Registers cited: Census Bureau — Surname Frequency 2010; Surnames of England and Wales (taliesin-arlein.net, Sept 2002 electoral register); INE — Padrón per-token widgets (current living counts, given + apellidos); INE — Apellidos más frecuentes (Padrón Municipal). Figures without a register are Mondonomo estimates; see Methodology.
Country figures for a list of names, at full precision, are available under licence rather than by scraping this table (how that works).
Notable people with this name
(measured from records)- Mark O'Halloranb. 1901not in their usual nameIrish actor and scriptwriter
- Michael O'Halloranb. 1933IEnot in their usual nameBritish politician (1933-1999)
- Kevin O'Halloranb. 1937AUnot in their usual nameAustralian swimmer, Olympic gold medallist (1937–1976)
- Jack O'Halloranb. 1943USnot in their usual nameAmerican boxer, actor
- Maura O'Halloranb. 1955FRnot in their usual nameAmerican Buddhist nun
- Vicki O'Halloranb. 1964AUnot in their usual nameAustralian businesswoman; Administrator of the Northern Territory
- Brian O'Halloranb. 1969USnot in their usual nameAmerican actor and producer
- Dustin O'Halloranb. 1971USnot in their usual nameAmerican musician
- Stephen O'Halloranb. 1987IEnot in their usual nameIrish footballer
- Tom O'Halloranb. 1992AUnot in their usual nameAustralian climber
The ten people covered by the most Wikipedia language editions — a proxy for cross-cultural notability, which favours historical and Western figures over equally prominent contemporary ones — shown by birth year. Source: Wikidata (CC0).
How to address them
(machine-generated)Evidence
(measured from records)10 registers and reference works attest this spelling, across 6 countries.
| Country | Register | Year | Count | Rank |
|---|---|---|---|---|
| GB United Kingdom | Surnames of England and Wales (taliesin-arlein.net, Sept 2002 electoral register) | 2002 | 2.2K | #3,363 |
| ES Spain | INE — Apellidos más frecuentes (Padrón Municipal) | — | 42 | #50,832 |
| US United States | wru Name Dictionary — US surnames, voter-file supplement (Khanna et al.) | — | — | — |
Reference works 3
- Nederlandse FamilienamenBank (Dutch surname bank; ex-Meertens Instituut, now CBG)2007
- Wikipedia surname tokens
- Wikidata name items (native-script + romanized given/family names)
These works list the name; their figures are licensed and are not reproduced here.
Register rows as of the 2026-10-09 data build.
Frequently asked questions
- What does the name O'Halloran mean, and where does it come from?
- Descendant of Halloran. Recorded by Encyclopedia of surnames [the complete companion to tracing your names history].
- How do you pronounce O'Halloran?
- A machine transcription gives /oʊˈhæɫɝən/ (IPA) for English.
- In which country does O'Halloran have the most bearers?
- In the United States, the national register counted about 5.5 thousand people named Halloran, more than in any other country we hold.
- How common is the name O'Halloran?
- In Spain, the national register counted 13 people named O'Halloran, about 1 in 3.8 million residents.
- How common is O'Halloran compared with other names?
- In Ireland, O'Halloran is the 444th most common surname of 73,729 surnames recorded there.
What do you want to know about O'Halloran?
Nobody replies to these one by one, but what readers ask decides what these pages answer next.
Query this name via API
curl -H "X-API-Key: YOUR_KEY" https://api.mondonomo.ai/api/v1/name-graph/o'halloranThe payload this page is built from: spellings and scripts, countries and languages, related names, and the registers that attest the form. It takes a free API key (1,000 requests a day), which returns what this page shows everyone; the full country table, every register citation and the year-by-year series come with a licensed key, as does bulk access.
About this data
measured from records inferred from the name graph machine-generated
These figures come from the data snapshot of and will change as it is rebuilt.
Statistics are aggregated from the Mondonomo name corpus; related names and etymology are inferred from the name graph; pronunciation and any machine-marked transliterations are model-generated. Read how the numbers are made, including their known failure modes, and where the data comes from.
Reference works we consult — surname dictionaries, official name registers, Wikidata and Wiktionary — are named directly, beside the claims they support. The per-country source counts also include datasets of person records: we publish how many there are and their authority tier, but not their names.
Cite this page Mondonomo, “O'Halloran” — the 444th most common surname in Ireland. Data snapshot 2026-10-13.