Photo: David Purchase · CC BY-SA 2.0In Trefor, 52% of households live in a terraced house, more than in 98% of UK towns
Shared households of unrelated adults make up 0.5%, against 3.1% across Wales’s towns. Trefor is home to 448 residents in 201 households, by the 2021 Census. One-person households: 39% of the total. 7.9% of residents are aged 15 to 24, a lower share than in 93% of UK towns.
Trefor is older than 52% of UK towns: a median age of 44.8
Share of residents in each five-year age band, Census 2021.
The largest age band is 55–59: 8.1% of residents. Fewer residents aged 65 and over than in 51% of UK towns: 22%. In Tywyn, the oldest of Gwynedd’s towns by this measure, it is 36%.
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.
Trefor sits below 96% of UK towns for full-time students (3.4%)
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%.
Across Wales’s towns, 29% of adults are in managerial and professional jobs and 27% in routine or semi-routine work; Trefor has 25% and 37%. Elsewhere, 8% of adults are full-time students across Wales’s towns. For Trefor, the census puts residents who moved in within the year at 7.6%.
Trefor ranks below 77% of UK towns on households with dependent children: 24%
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.
A household here has 2.2 people on average; across Wales’s towns, 2.3. Typically, 27% of households have dependent children across Wales’s towns.
4.5% of households live in a flat or apartment, below 85% of UK towns
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
Households without a car or van: 20% here and 21% across Wales’s towns. Across the comparison, 14% of households live in a flat or apartment across Wales’s towns. In Trefor, just over a fifth of households live in a detached house.
Trefor ranks below 65% of UK towns on residents born outside the UK: 4.9%
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
Residents born abroad were most often born in EU countries (2%), then in the Americas, Oceania and elsewhere (1.1%). 98% of residents have English as their main language, a higher share than in 55% of UK towns. The wider picture: 7.4% of residents were born outside the UK across Wales’s towns.
In Trefor, Welsh is a language for 75% of residents
Welsh language skills, residents aged 3 and over, Census 2021.
Welsh language skills · residents aged 3 and over
75% of residents aged 3 and over, 331 people, said in 2021 that they can speak Welsh, more than in 98% of Welsh towns (Welsh towns: 16%). Caernarfon leads Gwynedd with 82%.
Residents who describe themselves as White British: 96%, a higher share than 83% 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: 96% of Trefor · Gwynedd’s towns 93% · Wales’s towns 90%.
Religion · all residents
The largest groups after White British are Other White (3.6%), Chinese (0.5%) and Pakistani (0.2%). Trefor has fewer residents who describe themselves as Christian than 76% of UK towns, at 46%. As a yardstick, nine in ten residents describe themselves as White British across Wales’s towns. With residents with no religion at 45%, Trefor is ahead of 75% of UK towns on that count.
Below 89% of UK towns: 41% of adults are married or in a civil partnership
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
Across Wales’s towns, 38% of adults have never married or formed a civil partnership; in Trefor, 40%. Some 18 people give 50 hours or more of unpaid care a week. On unpaid carers, Trefor sits higher than 55% of UK towns: 9.5%. Against that, 43% of adults are married or in a civil partnership across Wales’s towns.
Qualified to degree level: 28% of adults
Highest qualification, residents 16 and over, Census 2021.
Highest qualification · residents 16 and over
Across Wales’s towns, 31% of adults have a degree-level qualification; in Trefor, 28%, and 21% have none, against 20%.
Every neighbour of Trefor has an older population
Nearby built-up areas coloured by median age, Census 2021. Tap a town for its page.
Health, work and homes have their own pages
What this data can and can’t tell you
- “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 Trefor’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 Trefor’s residents
What is the population of Trefor?
The 2021 Census counted 448 people in Trefor’s built-up area.
What is the average age in Trefor?
The median age was 44.8 at the 2021 Census. 7.9% of residents were 15 to 24 and 22% were 65 or over.
How diverse is Trefor?
96% of residents described themselves as White British in 2021, against 90% across Wales’s towns and 93% across Gwynedd’s towns. 4.9% were born outside the UK.
What religion are people in Trefor?
45% said they had no religion and 46% that they were Christian at the 2021 Census; 0.2% were Muslim and 7.6% didn’t answer.
Is Trefor good for families?
24% of households had dependent children in 2021, against 27% across Wales’s towns. Schools are on Trefor’s schools page.
How many people speak Welsh in Trefor?
331 residents aged 3 and over, 75%, 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.