Portmarnock has a population of 9,285, making it the 76th largest place we list in Ireland. It is in Leinster.
Portmarnock holds 0.17% of Ireland's 5,356,950 people. Dublin, the largest place we list there, is 110 times its size. Twenty years earlier the World Gazetteer recorded 8,037, a rise of 16%.
The population, measured on the census's boundary
| What you mean | Population | Source |
|---|---|---|
| Portmarnock the CSO Built Up Area: the continuously built-up town | 10,750 | Census 2022 |
| Portmarnock (GeoNames record) the figure in this page's heading; boundary unstated | 9,285 | GeoNames |
The census figure is the CSO's Census 2022 count for the Built Up Area, the boundary the CSO itself reports town populations on (data: CSO and Tailte Éireann, CC BY 4.0). Where the rows disagree, quote the census.
The 2005 figure comes from the World Gazetteer archive restored on this site. The two sources may draw the settlement's boundary differently, so treat the change as indicative rather than exact. Why figures differ.
Portmarnock is in Leinster, which has 256 recorded places.
Nearby in size
| Place | Region | Population |
|---|---|---|
| Tuam | Connacht | 9,647 |
| Ballyboden | Leinster | 9,611 |
| Trim | Leinster | 9,563 |
| An Ros | Leinster | 9,231 |
| Balally | Leinster | 9,051 |
| Ratoath | Leinster | 9,043 |
All places in Ireland → · Leinster →
Figures are the latest available in GeoNames (CC BY 4.0), which draws on national censuses of varying dates — treat them as recent, not same-year. Country totals are UN World Population Prospects 2024 (medium variant) where the UN lists the country separately; the handful it reports under a parent state keep a GeoNames figure and are marked as such. Sources & method.