Photo: Laurel Lodged · CC BY-SA 4.0A lower share of residents aged 15 to 24 than 99% of Irish towns, at 7.9%
Flats are home to 30% of households, against 12% across Ireland’s towns. The 2022 Census counted 6,355 residents in 2,262 households. In Castleknock, 16% of households are one person living alone. 6.6% of households are unrelated adults sharing a home, more than in 67% of Irish towns.
What stands out about the people of Castleknock
Growing faster than most
Castleknock went from about 5,330 people in 2016 to 6,355 in 2022, +19%: faster growth than in 89% of Irish towns. Population change ↓
Written from the data on this page: CSO Census 2022.
From 2016 to 2022, Castleknock outgrew 89% of Irish towns: +19%
Residents at the 2016 and 2022 censuses, on 2022 boundaries, and the change beside the county’s towns and Ireland’s.
Change, 2016 to 2022
CSO publishes yearly population estimates for counties and regions, not towns, so the trend is two censuses rather than a line; 2016 ages aren’t on 2022 boundaries, so there is no change by age.
The median change is +8% across Ireland’s towns and +6% across Co. Dublin’s towns.
18% of residents are 65 or over, more than in 80% of Irish towns
Share of residents in each five-year band; the tick is the typical town.
The biggest five-year age group is 30–34, with nearly one in ten residents, 1.4 times the share across Ireland’s towns. As a yardstick, 14% of residents are 65 or over across Ireland’s towns. With a median age of 38.1, Castleknock is older than 56% of Irish towns.
Median age of Irish towns of 2,500+
■ Castleknock, 38.1. The typical town is 37.6.
Broad ages · share of residents
Women and men · all residents
50% women, 50% men
About an even split. Median share of women: Co. Dublin 51.4%, Ireland 51.2%.
More residents who moved in within the year than 84% of Irish towns: 12%
CSO’s social classes (everyone, by their own or their family’s occupation), the occupations of those at work, and where residents lived a year before the Census.
Residents by social class · all residents
Where residents lived a year earlier
Residents who lived somewhere else a year earlier. The bar runs to 25%.
Workers by occupation · residents at work
8.7% of residents 15 and over are students; across Ireland’s towns the figure is 10%. Across Ireland’s towns, residents who moved in within the year come to 7.5%.
Castleknock households average 2.7 people, larger than in 61% of Irish towns
Private households by CSO’s family types, beside the county’s towns and Ireland’s.
Against Co. Dublin’s towns and Ireland’s towns
People per household
Ireland’s towns.
Against a figure of 43% across Ireland’s towns, the share of households of parents with children in Castleknock comes in at 41%.
Castleknock sits below 81% of Irish towns for households without a car or van (8.7%)
Home types, cars and the internet, by household. Owning and renting are on Cost of living.
Type of home
Cars or vans · share of households
Internet at home · share of households
No internet at all: 1.6% (typical: 7.6%). The benchmark for households without a car or van across Ireland’s towns: 17%. Broadband: 98% of households. At 0.3%, the share of holiday homes is higher than in 58% of Irish towns.
A median household income of €109,590 a year
Household income in 2022 from CSO’s linked administrative data (GPIIA): the middle household’s income before and after tax.
Gross household income has a median of €109,590 a year here, 82% above Ireland (€60,120). Co. Dublin comes in at €71,120 at the median.
A larger share of residents with another country’s citizenship than 65% of Irish towns: 18%
Place of birth and citizenship as CSO asks them: born abroad includes Irish citizens born abroad.
Born abroad, by birthplace · share of all residents; the bar runs to 30%
Citizenship · share of all residents; the bar runs to 30%
Citizens of another country, by citizenship; CSO counts dual Irish citizens as Irish.
Other languages · share of all residents
CSO’s small-area tables don’t give the year people arrived.
The share of residents born outside Ireland is 25%, against 22% across Ireland’s towns. The wider picture: 15% of residents are citizens of another country across Ireland’s towns. 20% speak a language other than English at home, Spanish most of all (1.8%); 2.6% speak English not well or not at all.
Irish speakers: 48% of Castleknock’s residents
Residents aged 3 and over who can speak Irish, and how often they speak it outside education (CSO).
Irish speakers · residents aged 3 and over
Within Co. Dublin, Monkstown has the largest share, 2.5%. 1.2% of residents speak Irish daily outside education, a higher share than in 59% of Irish towns.
70% of residents said they are Catholic, fewer than in 57% of Irish towns
Ethnic or cultural background and religion, in CSO’s categories, as people described themselves.
Ethnic groups other than White Irish · all residents
White Irish, not charted: 77% of Castleknock · Co. Dublin’s towns 78% · Ireland’s towns 78%.
Religion · all residents
Leading the other groups after White Irish: Other White (12%), Asian or Asian Irish (6%) and Other, including mixed (2.8%). Few places have so few residents who describe themselves as White Irish: 77% here, fewer than in 52% of Irish towns. Measured more widely, 71% of residents said they are Catholic across Ireland’s towns. Castleknock sits close to the norm on residents with no religion: 17%, about the same as across Ireland’s towns.
A larger share of married residents 15 and over than 98% of Irish towns: 45%
Marital status of residents 15 and over, and unpaid carers.
Partnership status · residents 15 and over
The small-area tables count carers, not their hours of care.
Unpaid carers account for 5.5%. 48% of Castleknock’s residents 15 and over are single and 45% married, against 56% and 34% across Ireland’s towns.
Castleknock sits above 97% of Irish towns for adults with a degree or higher (65%)
Highest level of education completed, residents 15 and over whose education has ended.
Highest qualification · residents 15+ whose education has ended
Postgraduate: 31% of adults. Against that, 36% of adults whose education has ended hold a degree or higher across Ireland’s towns. Primary level or earlier: 3.1%, against 9.7% across Ireland’s towns.
Of 41 towns its size (5,568 to 7,209 people), the 18th oldest
Median age of the Irish towns nearest in population; hover a dot.
Ages run from 25.6 in Gillabbey to 45.4 in Sutton. Nearest to Castleknock in age: Christchurch (37.7), Loughrea (37.9), Roscommon (38.3) and Kells (38.4).
2 of the 6 nearest towns are older than Castleknock
The nearest places, coloured by median age; each is a census neighbourhood.
| Town | People | Away | Median age | 65+ | Parents with children |
|---|---|---|---|---|---|
| Castleknock | 6,355 | — | 38.1 | 18% | 41% |
| Ashtown | 14,937 | 2.3 km | 36.5 | 12% | 40% |
| Carpenterstown | 20,967 | 2.4 km | 37.4 | 11% | 52% |
| Blanchardstown | 24,613 | 2.6 km | 37.3 | 14% | 45% |
| Finglas South | 12,475 | 3.0 km | 37 | 14% | 44% |
| Chapelizod | 4,862 | 3.3 km | 38.9 | 16% | 22% |
| Ballyfermot | 3,632 | 3.5 km | 38.8 | 17% | 41% |
Health, work, housing and schools
What this data can and can’t tell you
- Against Co. Dublin’s towns and Ireland’s towns. Each comparison is its own median: over Co. Dublin’s towns of 2,500 or more and over the Irish towns of 2,500 or more (city totals left out). Percentiles are within Ireland only.
- The earlier population is an estimate. Towns had no official 2016 count on today’s boundaries, so the 2016 figure is CSO’s electoral-division count shared out by where people lived in 2022: read a small town in a large rural division loosely.
- What these tables don’t give. The small-area tables give no year of arrival and no hours of care, and a town’s electoral divisions run past its edge, so the page doesn’t split a town into named areas (a city lists its neighbourhoods).
- The census’s own words. Born abroad, citizenship, ethnic or cultural background and religion are CSO’s questions and categories; the page compares them with other towns and never labels a town by them.
- Neighbourhoods are sums of small areas. Neighbourhood figures are TownRatings sums of CSO Small Areas
Questions about Castleknock’s residents
What is the population of Castleknock?
Castleknock had 6,355 residents at the 2022 Census, counted within its neighbourhood, 19% more than 2016.
What is the average age in Castleknock?
The median age is 38.1, older than 56% of Irish towns. 23% are under 18 and 18% 65 or older.
How many people speak Irish in Castleknock?
48% of residents aged 3 and over can speak Irish (2,760 people), and 1.2% speak it every day outside education, against a typical 1.1% across Ireland’s towns.
How diverse is Castleknock?
77% describe themselves as White Irish (Ireland’s towns: 78%); 25% were born abroad and 18% are citizens of another country.
What religion are people in Castleknock?
70% are Catholic, 17% have no religion and 13% another religion; 5.8% didn’t say.
Is Castleknock good for families?
41% of households are parents with children (Ireland’s towns 43%), and 23% of residents are under 18. Schools near Castleknock are on its Schools page.
What is the median income in Castleknock?
Median gross household income in Castleknock was €109,590 in 2022, against €71,120 across Co. Dublin and €60,120 for Ireland.
Sources: CSO, Census of Population 2022, Small Area Population Statistics · CSO PxStat FP009 (2016 by electoral division) · CSO GPIIA, household income 2022 · Neighbourhood figures are TownRatings sums of CSO Small Areas. Under Creative Commons Attribution 4.0 (CC BY 4.0).
Contains Central Statistics Office (CSO) data, Census 2022, and Tailte Éireann boundaries (CSO Urban Areas, Small Areas, local electoral areas, constituencies), under Creative Commons Attribution 4.0 (CC BY 4.0).