Photo: David Medcalf · CC BY-SA 2.0A higher share of households in terraced houses than 99% of UK towns, at 75%
Flats are home to 0.7% of households, against 14% across Wales’s towns. Llanllyfni is home to 352 residents in 152 households, by the 2021 Census. The share of residents aged 65 and over stands at 17%. Few places have as many adults who have never married: 41% here, more than in 93% of UK towns.
A median age of 39.6: Llanllyfni is younger than 82% of UK towns
Share of residents in each five-year age band, Census 2021.
Llanllyfni sits close to the norm on residents aged 15 to 24: 12%, about the same as across Wales’s towns. The largest age band is 0–4: 7.7% of residents, 1.5 times the share across Wales’s towns.
Broad ages · share of residents
Women and men · all residents
52% women, 48% men
About 91 men for every 100 women. Across Wales, 51% of residents are women.
A lower share of residents who moved in within the year than 97% of UK towns, at 6%
What adults did at the 2021 Census (the ONS’s NS-SEC classes), and where residents lived a year earlier.
Adults by occupation class · residents 16 and over
Address a year before the Census
Residents who lived somewhere else a year earlier. The bar runs to 25%.
6.6% of adults are full-time students; across Wales’s towns the figure is 8%. Across Wales’s towns, the share of residents who moved in within the year is 9.1%.
The Census was taken on 21 March 2021, in term time, so students were counted at their term addresses.
A lower share of households with dependent children than 72% of UK towns, at 25%
Household make-up at the 2021 Census. Each square is 1% of households.
Against Gwynedd’s towns and Wales’s towns
People per household
Wales’s towns.
Compared with 32% across Wales’s towns, 33% of households are one person living alone here. For Llanllyfni, the census puts shared households of unrelated adults at 4%. The usual figure: 27% of households have dependent children across Wales’s towns.
Only 11% of households in Llanllyfni live in a detached house
Accommodation type and cars or vans per household, Census 2021. Owning and renting are on Cost of living.
Type of home
Cars or vans · share of households
Here nearly a fifth of households have no car or van, where the figure across Wales’s towns is 21%. To put it in context, nearly a quarter of households live in a detached house across Wales’s towns.
Fewer residents born abroad than 89% of UK towns: 3.1%
Country of birth, year of arrival and main language, Census 2021.
Born outside the UK, by region · share of all residents; the bar runs to 10%
Main language · residents aged 3 and over
The two biggest birthplaces abroad are in the Americas, Oceania and elsewhere (1.7%) and in EU countries (1.1%). The share of residents born outside the UK across Wales’s towns is 7.4%. Llanllyfni has more residents whose main language is English than 97% of UK towns, at 99%.
80% of residents speak Welsh in Llanllyfni
Welsh language skills, residents aged 3 and over, Census 2021.
Welsh language skills · residents aged 3 and over
Asked in 2021, 268 residents aged 3 and over, 80%, said they can speak Welsh; across Welsh towns, 16%: more than in 99% of Welsh towns. In Gwynedd, Caernarfon has the highest share (82%).
Residents who describe themselves as White British make up 95% in Llanllyfni, more than in 82% of UK towns
How residents described themselves at the 2021 Census. Lines join the lowest and highest of the three figures.
Ethnic groups other than White British · all residents
White British, not charted: 95% of Llanllyfni · Gwynedd’s towns 93% · Wales’s towns 90%.
Religion · all residents
Residents who describe themselves as Christian: 42% here and 43% across Wales’s towns. The census found that 48% of residents said they have no religion in Llanllyfni. Across Wales’s towns, the share of residents who describe themselves as White British is 90%.
Llanllyfni: 11% of residents give unpaid care, above 92% of UK towns
Legal partnership status (residents 16 and over) and unpaid care (residents 5 and over), Census 2021.
Partnership status · residents 16 and over
Unpaid care given · share of residents 5 and over
Students and young renters account for much of that. Married adults and civil partners account for 43%.
Degree level: the highest qualification of 29% of adults
Highest qualification, residents 16 and over, Census 2021.
Highest qualification · residents 16 and over
With 29% of its adults qualified to degree level, Llanllyfni compares with 31% across Wales’s towns; another 14% hold no qualification (20%). A levels are the highest qualification of 22%, many of them students still working towards a degree.
Median age: 5 of the 7 towns around Llanllyfni are older
Nearby built-up areas coloured by median age, Census 2021. Tap a town for its page.
| Town | People | Away | Median age | 65+ | Homes with children |
|---|---|---|---|---|---|
| Llanllyfni | 352 | — | 39.6 | 17% | 25% |
| Penygroes | 1,793 | 0.8 mi | 45.2 | 24% | 24% |
| Caernarfon | 9,831 | 6.7 mi | 39.6 | 19% | 28% |
| Llanrug | 1,537 | 8.2 mi | 41.2 | 22% | 34% |
| Llanberis | 1,838 | 8.3 mi | 44.5 | 20% | 25% |
| Criccieth | 1,737 | 8.7 mi | 56.6 | 37% | 18% |
| Bethel | 1,091 | 9.1 mi | 44.7 | 24% | 32% |
| Clwt-y-bont | 1,385 | 9.6 mi | 39 | 17% | 31% |
Health, work and homes have their own pages
What this data can and can’t tell you
- The Census was taken in a lockdown, in term time. 21 March 2021 fell in term time, and students were asked to give their term-time address, so most were counted where they study. Some may have been living with family that day.
- “Gwynedd’s towns” and “Wales’s towns” mean their built-up areas. Census comparisons pool every built-up area in Gwynedd (or Wales), summed the same way as Llanllyfni’s figures, so households in open countryside are left out.
- Small counts are blurred. The ONS adds small random changes to Census counts to protect privacy, so the same total differs a little between tables, and the shares of a small town can move by a point or two.
Questions about Llanllyfni’s residents
What is the population of Llanllyfni?
The 2021 Census counted 352 people in Llanllyfni’s built-up area.
What is the average age in Llanllyfni?
The median age was 39.6 at the 2021 Census. 12% of residents were 15 to 24 and 17% were 65 or over.
How diverse is Llanllyfni?
95% of residents described themselves as White British in 2021, against 90% across Wales’s towns and 93% across Gwynedd’s towns. 3.1% were born outside the UK.
What religion are people in Llanllyfni?
48% said they had no religion and 42% that they were Christian at the 2021 Census; 0% were Muslim and 9.1% didn’t answer.
Is Llanllyfni good for families?
25% of households had dependent children in 2021, against 27% across Wales’s towns. Schools are on Llanllyfni’s schools page.
How many people speak Welsh in Llanllyfni?
268 residents aged 3 and over, 80%, said they can speak Welsh at the 2021 Census, against 16% across Welsh towns.
Sources: ONS Census 2021, output areas summed to the ONS 2022 built-up area (TS002, TS003, TS004, TS007A, TS008, TS015, TS017, TS019, TS021, TS029, TS030, TS039, TS044, TS045, TS062, TS067, TS032). All under the Open Government Licence v3.0.
Contains public sector information licensed under the Open Government Licence v3.0. Contains HM Land Registry data © Crown copyright and database right 2026. Contains OS data © Crown copyright and database right 2026 (ONS boundaries). Northern Ireland: Source: NISRA; contains Land & Property Services data and Ordnance Survey of Northern Ireland information, © Crown copyright, licensed under the Open Government Licence v3.0. Scotland: contains National Records of Scotland data, Registers of Scotland data and SEPA data, © Crown copyright / © SEPA 2025, licensed under the Open Government Licence v3.0.