In Groslay, 36% of households are couples with children, more than in 94% of compared French towns
Just over a fifth of households are headed by a manager or professional, against 9.4% in the typical compared French town. In 2023, the Census found 8,453 residents in Groslay, living in 3,270 households. On the census count, 46% of homes are flats. Second homes are rarer here than in 86% of compared French towns.
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 Groslay
A town of families
36% of households are couples with children and 10% single parents with children; 20% of residents are under 15. Households ↓
Immigrants
INSEE counts 1,400 immigrants in Groslay (people born abroad who weren’t French at birth, whatever their nationality now): 16% of residents, against 16% for the median compared commune in Val-d'Oise. 11% are foreign nationals. Immigrants and foreign nationals ↓
A young town
Half of Groslay’s residents are under 37.9 and half over; the median of compared French towns is 44. 20% are under 15 and 14% are 65 or older. Ages ↓
Written from INSEE’s census 2023 on this page, against compared French towns.
Slower growth than 80% of compared French towns: Groslay changed by −3% since 2012
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
From 2012 to 2017 the change was +1%; from 2017 to 2023, −4%. Over the same years the median compared French town changed +5%, the median Val-d'Oise town +8%.
Groslay is younger than 89% of compared French towns: a median age of 37.9
Shares of residents by age at the 2023 census.
Age groups · share of residents
Median age of the 3,798 compared French towns
■ Groslay 37.9. The median compared French town: 44.
In the typical compared French town, the share of residents aged 15 to 24 is 11%; Groslay has 12%. At the same time, on residents aged 65 and over, Groslay sits lower than 93% of compared French towns: 14%.
Women and men · all residents
52% women, 48% men
About 93 men for every 100 women. Median share of women: Val-d'Oise 51.5%, France 51.8%.
A lower share of one-person households than 85% of compared French towns, at 28%
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
Households here average 2.5 people each. Compared with other places, single-parent households are common here: 10%, more than in 51% of compared French towns. Elsewhere, just over a third of households are one person living alone in the typical compared French town.
In Groslay, 9% of households rent social housing (HLM), fewer than in 65% 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
One household in seven has no car (median compared French town: 11%). The benchmark for households in social housing in the typical compared French town: 12%. Households without a car account for 14%. On empty homes, Groslay sits lower than 55% of compared French towns: 6.4%.
Median living standard: €29,630 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.
Per consumption unit, half of residents live on more than €29,630 a year: higher than in 82% of compared French towns. Below the poverty threshold: 14.0% of the population.
Households headed by a retired person make up 21% in Groslay, less than in 93% 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
14% of households are headed by a manual worker in the typical compared French town, against 9.2% in Groslay. Households headed by a retired person make up 32% in the typical compared French town.
Each household is counted once, by the occupation of its reference person (usually the oldest working adult).
A higher share of immigrants than 88% of compared French towns, at 16%
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.
By its share of foreign nationals (11%), Groslay is above 85% of compared French towns. As a yardstick, 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.
29% of residents 15 and over are single, a share 74% 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
Where 43% of residents 15 and over are married in the typical compared French town, Groslay has 46%. For single residents, the comparison in the typical compared French town is 25%.
Above 81% of compared French towns: 41% of adults out of school hold a higher-education qualification
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
Adults with no qualification come to 18% in Groslay, about two in ten. The benchmark for graduates of higher education in the typical compared French town: 30%.
Ranked by age, 2nd youngest of 41 French towns this size
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 Varces-Allières-et-Risset (35.8), the youngest, and La Grande-Motte (62.3), the oldest.
Around Groslay, 2 of 6 towns have a higher median age
The nearest towns of 2,500 or more, colored by median age. Source: INSEE, census 2023.
| Town | Median age | 65+ | Second homes | Immigrants |
|---|---|---|---|---|
| Groslay | 37.9 | 14% | 0.8% | 16% |
| Saint-Brice-sous-Forêt 15,063 · 0.9 mi | 35.7 | 15% | 0.9% | 18% |
| Montmagny 15,105 · 1.2 mi | 35.8 | 13% | 0.9% | 29% |
| Sarcelles 59,173 · 1.3 mi | 33.6 | 13% | 0.6% | 36% |
| Montmorency 21,763 · 1.4 mi | 41.4 | 19% | 2.1% | 17% |
| Deuil-la-Barre 23,099 · 1.6 mi | 39.1 | 16% | 1% | 24% |
| Villetaneuse 12,530 · 2 mi | 33.2 | 12% | 0.6% | 38% |
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 Groslay
What is the population of Groslay?
8,453 at INSEE’s 2023 census, 3% fewer than in 2012 (8,676).
How old are Groslay’s residents?
The median age is 37.9, younger than 89% of compared French towns. 24% are under 18 and 14% 65 or older.
How many second homes are there in Groslay?
29, with occasional dwellings: 0.8% of all homes, against 2.1% for the median compared French town.
How many immigrants live in Groslay?
INSEE counts 1,380 immigrants (born abroad, not French at birth), 16% of residents, and 950 foreign nationals (11%). The medians of compared French towns are 6.5% and 4.3%.
What is the median income in Groslay?
€29,630 a year per consumption unit in 2023 (median of compared French towns €25,970); 14.0% 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.