Only 1.5% of households have no car in Sergy
Households in social housing are rarer here than in 99% of compared French towns. Residents aged 15 to 24 account for 5.6%. Sergy had 139 residents in 63 households at the 2023 census. 43% of households are headed by a retired person (typical compared French town: 32%).
Throughout this page, the Aisne median and the France median are the median of compared communes (those with an overall grade), each figure its own median. Source: INSEE, census 2023.
What stands out about the people of Sergy
One home in five is a second home
The census counted 17 second homes and occasional dwellings in Sergy, 20% of its 84 homes: higher than in 93% of compared French towns. 100% of them are houses. Their owners live elsewhere, so they aren’t in the population figures on this page. Homes & cars ↓
Fewer residents than in 2012
Sergy had 162 residents at the 2012 census and 139 in 2023, down 14%: slower growth than in 99% of compared French towns. Population ↓
Written from INSEE’s census 2023 on this page, against compared French towns.
Above 93% of compared French towns: 20% of homes are second homes
Every home the census counted: main residences, second homes and occasional dwellings (INSEE counts them together), and empty homes. Owning and renting are on Cost of living.
All homes · share of homes
Type of home
Cars per household · share of households
Flats are rarer here than in 99% of compared French towns. The wider picture: 2.1% of homes are second homes in the typical compared French town. Here, 5% of homes stand empty.
Slower than most: −14% since 2012, behind 99% of compared French towns
Residents at INSEE’s last three censuses, each recast in the 2026 commune boundaries. France has no yearly estimate by commune between censuses.
2012 to 2023
2017 to 2023
Against +5% for the median compared French town and −4% for the median Aisne town, the change came in two steps: −7% from 2012 to 2017, then −8% to 2023.
Older than 75% of compared French towns: half of Sergy is over 48.2
Shares of residents by age at the 2023 census.
Age groups · share of residents
Median age of the 3,798 compared French towns
■ Sergy 48.2. The median compared French town: 44.
Just over a quarter of residents are 65 or over; in the typical compared French town the figure is 22%.
Women and men · all residents
55% women, 45% men
About 82 men for every 100 women. Median share of women: Aisne 52.5%, France 51.8%. Women live longer than men, so towns with many older residents have more women.
Sergy: 29% of households are couples with children, above 68% of compared French towns
A household is everyone who shares a main home (résidence principale). Household types come from INSEE’s fuller sample of a quarter of census forms.
Against the Aisne median and the France median
Living alone · share
Single-parent households are rarer here than in 99% of compared French towns. In the typical compared French town, the share of couples with children is 25%. Average household size: 2.2 people. The share of one-person households tops 53% of compared French towns: 36%.
Half of residents have a standard of living above €26,700 a year
The standard of living (niveau de vie) is a household’s disposable income after taxes and benefits, divided by its consumption units (UC) to allow for its size and make-up: 1 for the first adult, 0.5 for each other person 14 or older, 0.3 for each child under 14.
Medians of compared communes. Source: INSEE, Filosofi 2023.
Living standards centre on €26,700 a year per consumption unit: higher than in 58% of compared French towns.
Households headed by a manager or professional make up 21% in Sergy, more than in 90% of compared French towns
Households by the socio-professional group (PCS) of their reference person, INSEE’s own categories. Jobs and commuting are on the Work & commute page.
Households by reference person’s group · share of households
The share of households headed by a manual worker is 7.1%, against 14% in the typical compared French town. Measured more widely, 9.4% of households are headed by a manager or professional in the typical compared French town.
Each household is counted once, by the occupation of its reference person (usually the oldest working adult).
4.2% of residents are immigrants, fewer than in 72% of compared French towns
INSEE publishes two measures, which overlap but aren’t the same. Neither is the UK’s “born abroad”.
Share of residents · census 2023
Immigrant (immigré)
Born abroad, not French at birth. Someone stays an immigrant after becoming French. A French citizen born abroad (for example in Algeria before 1962) is not one.
Foreign national (étranger)
Not a French citizen today, wherever born. A child born in France to foreign parents can be a foreign national without being an immigrant.
In the typical compared French town, the share of foreign nationals is 4.3%; Sergy has 2.8%. On average, 6.5% of residents are immigrants in the typical compared French town.
INSEE publishes no country of birth or ethnicity by commune in these tables, and the census doesn’t ask about religion.
Only 14% of residents 15 and over are single in Sergy
Residents 15 and over by how they live: the census asks both the legal status and whether people live as a couple.
Residents 15 and over · share
43% of residents 15 and over are married in the typical compared French town, against 51% in Sergy. Single residents: 25% in the typical compared French town, for comparison.
Graduates of higher education: 25%, a lower share than 70% of compared French towns
Highest diploma of residents 15 and over who have left education, in French terms: the levels don’t map one-to-one to UK or U.S. ones.
Highest diploma · 15 and over, out of education
Here, 19% of adults out of school have no qualification. To put it in context, 30% of adults out of school hold a higher-education qualification in the typical compared French town.
Among 41 French towns of 139 to 2,582 people, the 15th oldest
The 40 compared French towns nearest in population, by median age. Hover for each one’s second homes and immigrants; click for its page.
At the ends of the range sit Villejust (37.2), the youngest, and Prayssac (62.3), the oldest.
2 of 6 neighbors are older than Sergy
The nearest towns of 2,500 or more, colored by median age. Source: INSEE, census 2023.
| Town | Median age | 65+ | Second homes | Immigrants |
|---|---|---|---|---|
| Sergy | 48.2 | 26% | 20% | 4.2% |
| Fère-en-Tardenois 2,836 · 2.9 mi | 47.8 | 28% | 1.9% | 3.3% |
| Dormans 2,890 · 8.2 mi | 48.9 | 28% | 3.7% | 4.9% |
| Fismes 5,850 · 10 mi | 43.6 | 23% | 1.5% | 3.1% |
| Château-Thierry 15,097 · 12.2 mi | 41.3 | 22% | 2.4% | 16% |
| Essômes-sur-Marne 2,691 · 14.2 mi | 44.5 | 21% | 2.3% | 9.6% |
| Belleu 3,659 · 16.4 mi | 51.5 | 31% | 1.4% | 11% |
Health, work, housing and schools
What this data can and can’t tell you
- Census 2023. INSEE’s census is a rolling survey: a fifth of small communes each year, 8% of homes in large ones each year. “2023” pools the surveys of 2021 to 2025, so the figures describe the town around 2023, not on one day.
- Medians of compared communes. The comparisons are the median of the département’s compared communes and of France’s (those with an overall grade), each figure its own median: not the total for the département or for France, which large cities pull towards their own figures.
- Immigrants and foreign nationals. INSEE’s two measures: an immigrant was born abroad without French nationality; a foreign national isn’t French today. Neither is a count of people born abroad, which INSEE doesn’t publish by commune.
- Second homes. Homes used for holidays or weekends, with occasional dwellings (kept for work, for example), which INSEE counts together. Their owners are counted where they live, not here.
- Standard of living. INSEE’s Filosofi: disposable income per consumption unit, from tax and benefit files, 2023. The poverty rate is the share of residents below 60% of France’s median. Not published for the smallest communes.
- What France doesn’t ask. The French census asks nothing about ethnicity, religion, language or health, so this page has no such section.
Questions about who lives in Sergy
What is the population of Sergy?
139 at INSEE’s 2023 census, 14% fewer than in 2012 (162).
How old are Sergy’s residents?
The median age is 48.2, older than 75% of compared French towns. 19% are under 18 and 26% 65 or older.
How many second homes are there in Sergy?
17, with occasional dwellings: 20% of all homes, against 2.1% for the median compared French town.
How many immigrants live in Sergy?
INSEE counts 6 immigrants (born abroad, not French at birth), 4.2% of residents, and 4 foreign nationals (2.8%). The medians of compared French towns are 6.5% and 4.3%.
What is the median income in Sergy?
€26,700 a year per consumption unit in 2023 (median of compared French towns €25,970). Source: INSEE, Filosofi.
Sources: INSEE, census 2023 (population, ages, households, homes, marital status, diplomas, immigrants, foreign nationals, employment), 2026 geography · INSEE, Filosofi 2023 (standard of living, poverty) · IGN Admin Express (boundaries) · Medians and percentiles: TownRatings, over compared French towns, updated November 4, 2026. Under the Licence Ouverte / Open Licence 2.0 (Etalab).
Contains public sector information under the Licence Ouverte / Open Licence 2.0 (Etalab): INSEE, DGFiP, the Interior Ministry’s statistics service (SSMSI), the Ministry of Education (DEPP), the Health Ministry’s statistics service (DREES) and the Housing Ministry (Carte des loyers). Commune boundaries: IGN Admin Express.