Photo: Peter Goodwin · CC BY-SA 2.0Maerdy ranks above 99% of UK towns on households in terraced houses: 66%
The share of households without a car or van is 36%, against 21% across Wales’s towns. Maerdy is home to 2,843 residents in 1,283 households, by the 2021 Census. In Maerdy, 13% of residents give unpaid care. One-person households are more common here than in 90% of UK towns.
What the Census says about Maerdy’s people
More with no religion than most
67% of residents answered “no religion” in 2021 and 26% Christian, against 47% and 43% across Wales’s towns. Ethnicity & religion ↓
Written from the data on this page: ONS Census 2021 (output areas summed to the 2022 built-up area) and ONS mid-year population estimates.
A change of +3% since 2011 leaves Maerdy behind 71% of UK towns
ONS mid-year estimates, each year indexed to mid-2011 = 100. Maerdy’s figure is the small areas (2021 LSOAs) that make up the town.
People, mid-2011 = 100
Change by age, 2011 to 2024
About 3,200 people in 2011; 3,300 in 2024.
The largest rise in a single year came from mid-2016 to mid-2017: 70 people. The 30 to 44 group saw the biggest change (+15%), the 45 to 64 group the smallest (−13%).
Half of Maerdy is under 41.7, younger than 71% of UK towns
Share of residents in each five-year age band, Census 2021.
Little separates the share of residents aged 15 to 24 here, 12%, from the figure across Wales’s towns. No age band is larger than 55–59: 7.4% of residents.
Median age of UK towns of 2,500+
■ Maerdy, 41.7. The typical town is 44.4.
Broad ages · share of residents
Women and men · all residents
51% women, 49% men
About 94 men for every 100 women. Across Wales, 51% of residents are women.
5.7% of adults are full-time students, more than in 78% of UK towns
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%.
Here 7.9% of residents lived at another address a year earlier, where the figure across Wales’s towns is 9.1%. Full-time students make up 8% across Wales’s towns.
The Census was taken on 21 March 2021, in term time, so students were counted at their term addresses.
2.2 people per household, fewer than in 67% of UK towns
Household make-up at the 2021 Census. Each square is 1% of households.
Against Mid Glamorgan’s towns and Wales’s towns
People per household
Wales’s towns.
The census found that 27% of households have dependent children in Maerdy. At 2.3%, shared households of unrelated adults sit close to the figure across Wales’s towns.
A smaller share of households in detached houses than 99% of UK towns: 3.3%
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
The share of households in flats is 13%, against 14% across Wales’s towns. Elsewhere, 24% of households live in a detached house across Wales’s towns.
A smaller share of residents born outside the UK than 98% of UK towns: 2.3%
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 whose main language is English: 99%, above 94% of UK towns. Typically, 7.4% of residents were born outside the UK across Wales’s towns.
8.1% of people in Maerdy speak Welsh
Welsh language skills, residents aged 3 and over, Census 2021.
Welsh language skills · residents aged 3 and over
At the 2021 Census, 224 residents aged 3 and over, 8.1%, said they can speak Welsh, against 16% across Welsh towns: fewer than in 86% of Welsh towns. The highest share in Mid Glamorgan belongs to Pontyclun (20%).
Residents with no religion make up 67% in Maerdy, more than in 99% 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: 98% of Maerdy · Mid Glamorgan’s towns 95% · Wales’s towns 90%.
Religion · all residents
Here 98% of residents describe themselves as White British, where the figure across Wales’s towns is 90%. 26% of residents describe themselves as Christian, a lower share than in 99% of UK towns. The wider picture: 47% of residents said they have no religion across Wales’s towns.
35% of adults are married or in a civil partnership, fewer than in 98% 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
44% of adults have never married or formed a civil partnership, against 38% across Wales’s towns. The comparison figure for married adults and civil partners is 43% across Wales’s towns.
16% of adults hold a degree-level qualification
Highest qualification, residents 16 and over, Census 2021.
Highest qualification · residents 16 and over
Degree-level qualifications cover 16% of adults in Maerdy, 31% across Wales’s towns; 36% have no qualification, against 20%.
Of 514 UK towns its size (2,500 to 4,000 people), the 81st youngest
Median age, Census 2021. Hover a dot for its students and residents born abroad; click for its page.
The youngest is Keele (20.6) and the oldest West Chiltington (63.1). Nearest to Maerdy in age: Markyate (41.6), Rhostyllen (41.6), Calverley (42.1) and Grassmoor (42.1).
5 in 7 nearby towns have a higher median age than Maerdy
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 |
|---|---|---|---|---|---|
| Maerdy | 2,843 | — | 41.7 | 21% | 27% |
| Treorchy | 7,645 | 1.5 mi | 44.2 | 22% | 26% |
| Ferndale | 4,301 | 1.7 mi | 45.4 | 24% | 26% |
| Rhondda | 13,271 | 2 mi | 42.3 | 20% | 27% |
| Treherbert | 5,427 | 2.5 mi | 43 | 22% | 25% |
| Tylorstown and Pontygwaith | 3,551 | 3 mi | 39.6 | 17% | 27% |
| Aberdare | 37,675 | 3.1 mi | 42.3 | 21% | 28% |
| Wattstown | 1,105 | 3.8 mi | 38.9 | 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.
- “Mid Glamorgan’s towns” and “Wales’s towns” mean their built-up areas. Census comparisons pool every built-up area in Mid Glamorgan (or Wales), summed the same way as Maerdy’s figures, so households in open countryside are left out. The population trend compares with the whole county and nation.
- Estimates since 2021 are modelled. The ONS builds mid-year estimates from the Census, births, deaths and migration records. Maerdy’s trend uses the small areas (2021 LSOAs) with most of their people inside it: 3,125 people in 2021, against 2,843 in the built-up area.
- 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 Maerdy’s residents
What is the population of Maerdy?
The 2021 Census counted 2,843 people in Maerdy’s built-up area. The ONS estimates the same small areas held 3,300 people in mid-2024, 3% more than in 2011.
What is the average age in Maerdy?
The median age was 41.7 at the 2021 Census, younger than 71% of UK towns. 12% of residents were 15 to 24 and 21% were 65 or over.
How diverse is Maerdy?
98% of residents described themselves as White British in 2021, against 90% across Wales’s towns and 95% across Mid Glamorgan’s towns. 2.3% were born outside the UK.
What religion are people in Maerdy?
67% said they had no religion and 26% that they were Christian at the 2021 Census; 0.1% were Muslim and 5.7% didn’t answer.
Is Maerdy good for families?
27% of households had dependent children in 2021, against 27% across Wales’s towns. Schools are on Maerdy’s schools page.
How many people speak Welsh in Maerdy?
224 residents aged 3 and over, 8.1%, 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) · ONS mid-year population estimates for 2021 LSOAs, mid-2011 to mid-2024. 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.