Photo: Chris Whippet · CC BY-SA 2.0Above 85% of UK towns: 21% of households live in a flat or apartment
Households with dependent children make up 31%, against 29% across England’s towns. 12% of households have no car or van. Adults who have never married are rarer here than in just over three quarters of UK towns. Seal had 1,616 residents in 666 households at the 2021 Census.
9.5% of residents are aged 15 to 24, fewer than in 60% of UK towns
Share of residents in each five-year age band, Census 2021.
The median age in Seal is 45.1, higher than in 54% of UK towns. Locally, just over a fifth of residents are 65 or over. Against that, 12% of residents are aged 15 to 24 across England’s towns. In St Mary's Bay, the oldest of Kent’s towns by this measure, it is 42%.
Broad ages · share of residents
Women and men · all residents
54% women, 46% men
About 85 men for every 100 women. Across England, 51% of residents are women.
Full-time students: 5.2%, a higher share than 64% 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%.
By class, 43% of adults are in managerial and professional jobs and 17% in routine and semi-routine work (England’s towns: 33% and 24%). The usual figure: 7.9% of adults are full-time students across England’s towns. Here, nearly one in ten residents lived at another address a year earlier.
The Census was taken on 21 March 2021, in term time, so students were counted at their term addresses.
2.3 people per household, more than in 65% of UK towns
Household make-up at the 2021 Census. Each square is 1% of households.
Against Kent’s towns and England’s towns
People per household
England’s towns.
32% of households are one person living alone, against 30% across England’s towns. In Seal, 2.9% of households are unrelated adults sharing a home.
A larger share of households in terraced houses than 60% of UK towns: 23%
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 detached houses stands at 28%. Across England’s towns, households in terraced houses come to 24%.
Seal ranks above 79% of UK towns on residents born outside the UK: 11%
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 25%
When those born abroad arrived
Main language · residents aged 3 and over
The newest arrivals, from 2017 or later, are 15% of those born abroad (against 21% across England’s towns). Few places have so few residents whose main language is English: 97% here, fewer than in nearly three fifths of UK towns. By way of comparison, 18% of residents were born outside the UK across England’s towns. The two biggest birthplaces abroad are in EU countries (4.5%) and in the Middle East and Asia (2.2%).
A lower White British share than 73% of UK towns: 87% of residents
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: 87% of Seal · Kent’s towns 82% · England’s towns 73%.
Religion · all residents
By its share of residents who describe themselves as Christian (51%), Seal is above just over three fifths of UK towns. Residents with no religion are rarer here than in half of UK towns. Leading the other groups after White British: Other White (6.7%), Mixed or multiple (2%) and Indian (1.5%).
Seal sits above 59% of UK towns for married adults and civil partners (49%)
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
Unpaid carers giving 50 hours or more a week: 26. Nearly one in ten residents give unpaid care, fewer than in 80% of UK towns. Across England’s towns, the share of married adults and civil partners is 44%.
The share of adults with a degree-level qualification: 40%
Highest qualification, residents 16 and over, Census 2021.
Highest qualification · residents 16 and over
With 40% of its adults qualified to degree level, Seal compares with 34% across England’s towns; another 18% hold no qualification (18%).
Around Seal, 4 of 7 towns have a higher median age
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 |
|---|---|---|---|---|---|
| Seal | 1,616 | — | 45.1 | 22% | 31% |
| Otford and Kemsing | 7,332 | 1.5 mi | 46.4 | 23% | 33% |
| Sevenoaks | 26,474 | 1.8 mi | 42 | 18% | 36% |
| Dunton Green | 3,241 | 2.2 mi | 36.3 | 12% | 34% |
| Ightham | 2,037 | 2.8 mi | 48 | 23% | 35% |
| Borough Green | 4,712 | 3.9 mi | 43.9 | 21% | 31% |
| Wrotham | 1,961 | 4 mi | 46.2 | 22% | 30% |
| West Kingsdown | 4,306 | 4.1 mi | 52.1 | 30% | 22% |
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.
- “Kent’s towns” and “England’s towns” mean their built-up areas. Census comparisons pool every built-up area in Kent (or England), summed the same way as Seal’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 Seal’s residents
What is the population of Seal?
The 2021 Census counted 1,616 people in Seal’s built-up area.
What is the average age in Seal?
The median age was 45.1 at the 2021 Census. 9.5% of residents were 15 to 24 and 22% were 65 or over.
How diverse is Seal?
87% of residents described themselves as White British in 2021, against 73% across England’s towns and 82% across Kent’s towns. 11% were born outside the UK.
What religion are people in Seal?
41% said they had no religion and 51% that they were Christian at the 2021 Census; 0.6% were Muslim and 5.2% didn’t answer.
Is Seal good for families?
31% of households had dependent children in 2021, against 29% across England’s towns. Schools are on Seal’s schools page.
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). 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.