Photo: Robin.barbacetto · CC BY-SA 4.0Couples with children: 39%, a higher share than 99% of compared French towns
With second homes at 0.7%, Méry-sur-Oise is behind 89% of compared French towns on that count. A fifth of households are headed by a retired person, fewer than in 94% of compared French towns. The 2023 Census put the town’s population at 9,983, in 3,800 households. Put another way, about one in eight: 13% of residents are 15 to 24.
Throughout this page, the Val-d'Oise 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 Méry-sur-Oise
A town of families
39% of households are couples with children and 10% single parents with children; 22% of residents are under 15. Households ↓
A young town
Half of Méry-sur-Oise’s residents are under 37.9 and half over; the median of compared French towns is 44. 22% are under 15 and 12% are 65 or older. Ages ↓
Immigrants
INSEE counts 1,500 immigrants in Méry-sur-Oise (people born abroad who weren’t French at birth, whatever their nationality now): 15% of residents, against 16% for the median compared commune in Val-d'Oise. 12% are foreign nationals. Immigrants and foreign nationals ↓
Written from INSEE’s census 2023 on this page, against compared French towns.
From 2012 to 2023, Méry-sur-Oise outgrew 60% of compared French towns: +7%
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
In two steps, +6% to 2017 and +1% after, the town’s change compares with +5% for the median compared French town and +8% in Val-d'Oise.
12% of residents are 65 or over, fewer than in 97% of compared French towns
Shares of residents by age at the 2023 census.
Age groups · share of residents
Median age of the 3,798 compared French towns
■ Méry-sur-Oise 37.9. The median compared French town: 44.
Half of Méry-sur-Oise’s residents are under 37.9, younger than in 89% of compared French towns. In the typical compared French town, 22% of residents are 65 or over.
Women and men · all residents
51% women, 49% men
About an even split. Median share of women: Val-d'Oise 51.5%, France 51.8%.
Only 25% of households are one person living alone in Méry-sur-Oise
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 Val-d'Oise median and the France median
Living alone · share
The average household has 2.6 people. One in ten households are single parents, more than in 52% of compared French towns. In the typical compared French town, one-person households come to 35%.
Households in social housing make up 17% in Méry-sur-Oise, more than in 69% of compared French towns
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
Empty homes are about as common here as in the typical compared French town, at 7.6%. In the last two years, 10% of households moved in; at the other end, 16% have stayed 30 years or more. More flats than in 58% of compared French towns: 35%. The wider picture: just over one in ten households rent social housing (HLM) in the typical compared French town.
€29,380 a year: the median standard of living
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.
Half of residents live in households above €29,380 a year per consumption unit and half below; the level is higher than in 81% of compared French towns. The share living below the poverty line is 12.0%.
Méry-sur-Oise: 17% of households are headed by a manager or professional, above 83% 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
Census figures put households headed by a manual worker at 14% in Méry-sur-Oise. Households headed by a manager or professional: 9.4% in the typical compared French town, for comparison.
Each household is counted once, by the occupation of its reference person (usually the oldest working adult).
Méry-sur-Oise sits above 85% of compared French towns for immigrants (15%)
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.
12% of residents are foreign nationals (typical compared French town: 4.3%). Typically, 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.
28% of residents 15 and over are single, a share 66% of compared French towns don’t reach
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
The share of married residents is 44%, against 43% in the typical compared French town. Elsewhere, 25% of residents 15 and over are single in the typical compared French town.
Méry-sur-Oise ranks above 75% of compared French towns on graduates of higher education: 38%
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
Against a figure of 19% in the typical compared French town, the share of adults with no qualification in Méry-sur-Oise comes in at 16%. Across the comparison, 30% of adults out of school hold a higher-education qualification in the typical compared French town.
41 French towns of 9,839 to 10,160 people: this is the 6th youngest
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 Pierrelaye (35.2), the youngest, and Saint-Laurent-de-la-Salanque (54.6), the oldest.
Older than Méry-sur-Oise: 3 of the 6 towns nearby
The nearest towns of 2,500 or more, colored by median age. Source: INSEE, census 2023.
| Town | Median age | 65+ | Second homes | Immigrants |
|---|---|---|---|---|
| Méry-sur-Oise | 37.9 | 12% | 0.7% | 15% |
| Auvers-sur-Oise 6,863 · 1.1 mi | 44.3 | 20% | 3.4% | 9.4% |
| Frépillon 3,317 · 1.3 mi | 39 | 14% | 0.7% | 8.2% |
| Mériel 5,347 · 1.7 mi | 41.3 | 16% | 1.3% | 8.9% |
| Bessancourt 8,869 · 2.1 mi | 36.9 | 15% | 1% | 15% |
| Pierrelaye 10,130 · 2.8 mi | 35.2 | 12% | 0.8% | 20% |
| Saint-Ouen-l'Aumône 25,578 · 3 mi | 35.3 | 12% | 0.6% | 25% |
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 Méry-sur-Oise
What is the population of Méry-sur-Oise?
9,983 at INSEE’s 2023 census, 7% more than in 2012 (9,320).
How old are Méry-sur-Oise’s residents?
The median age is 37.9, younger than 89% of compared French towns. 26% are under 18 and 12% 65 or older.
How many second homes are there in Méry-sur-Oise?
30, with occasional dwellings: 0.7% of all homes, against 2.1% for the median compared French town.
How many immigrants live in Méry-sur-Oise?
INSEE counts 1,510 immigrants (born abroad, not French at birth), 15% of residents, and 1,230 foreign nationals (12%). The medians of compared French towns are 6.5% and 4.3%.
What is the median income in Méry-sur-Oise?
€29,380 a year per consumption unit in 2023 (median of compared French towns €25,970); 12.0% of residents live below the poverty line. 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.