Half of Liettres is under 34.1, younger than 98% of compared French towns
The share of flats trails 99% of compared French towns: 1.5%. The 2023 Census counted 378 residents in 130 households. About one in six: that is how common one-person households are in Liettres (17%). Compared with other places, households headed by a retired person are scarce here: 21%, fewer than in 94% of compared French towns.
Throughout this page, the Pas-de-Calais 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 Liettres
A young town
Half of Liettres’ residents are under 34.1 and half over; the median of compared French towns is 44. 25% are under 15 and 8.9% are 65 or older. Ages ↓
A town of families
38% of households are couples with children and 8.3% single parents with children; 25% of residents are under 15. Households ↓
Growing fast
Liettres had 296 residents at the 2012 census and 378 in 2023, up 28%: faster growth than in 96% of compared French towns. Population ↓
Written from INSEE’s census 2023 on this page, against compared French towns.
From 2012 to 2023, Liettres outgrew 96% of compared French towns: +28%
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
The median Pas-de-Calais town changed −1% and the median compared French town +5%; here the first five years brought +10% and the next six +16%.
8.9% of residents are 65 or over, below 99% 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
■ Liettres 34.1. The median compared French town: 44.
In the typical compared French town, the share of residents aged 15 to 24 is 11%; Liettres has 16%. Against that, 22% of residents are 65 or over in the typical compared French town.
Women and men · all residents
47% women, 53% men
About 111 men for every 100 women. Median share of women: Pas-de-Calais 52.0%, France 51.8%.
A larger share of couples with children than 97% of compared French towns: 38%
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 Pas-de-Calais median and the France median
Living alone · share
In the typical compared French town, 10% of households are single parents; in Liettres, 8.3%. Households average 3 people. The usual figure: a quarter of households are couples with children in the typical compared French town.
A lower share of households without a car than 99% of compared French towns, at 2.4%
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
The share of empty homes is 5.2%, against 6.7% in the typical compared French town. In the last two years, 7.2% of households moved in; at the other end, 15% have stayed 30 years or more. Set beside that, 11% of households have no car in the typical compared French town.
Median standard of living: €24,090 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.
Half of residents live in households above €24,090 a year per consumption unit and half below; the level is lower than in 70% of compared French towns.
Liettres sits above 99% of compared French towns for households headed by a manual worker (29%)
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
Each household is counted once, by the occupation of its reference person (usually the oldest working adult).
0% of residents in Liettres are immigrants
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.
Immigrants are rarer here than in 99% of compared French towns.
INSEE publishes no country of birth or ethnicity by commune in these tables, and the census doesn’t ask about religion.
A lower share of married residents than 79% of compared French towns, at 38%
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
Single residents: 26% of the total. Against that, 43% of residents 15 and over are married in the typical compared French town.
8.9% of adults out of school have no qualification, below 97% 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
Graduates of higher education account for 30%. Set beside that, nearly a fifth of adults out of school have no qualification in the typical compared French town.
The youngest of 41 French towns of 378 to 2,582 people
The 40 compared French towns nearest in population, by median age. Hover for each one’s second homes and immigrants; click for its page.
Ages run from 34.1 in Liettres to 62.3 in Prayssac.
Every neighbor is older than Liettres
The nearest towns of 2,500 or more, colored by median age. Source: INSEE, census 2023.
| Town | Median age | 65+ | Second homes | Immigrants |
|---|---|---|---|---|
| Liettres | 34.1 | 8.9% | 2.2% | 0% |
| Aire-sur-la-Lys 9,598 · 3.9 mi | 45.5 | 22% | 0.4% | 1% |
| Isbergues 8,650 · 5.4 mi | 46.1 | 25% | 1.2% | 0.8% |
| Lillers 10,193 · 6.4 mi | 40.8 | 20% | 0.5% | 1.9% |
| Burbure 2,834 · 6.8 mi | 43.1 | 20% | 1.2% | 0.7% |
| Cauchy-à-la-Tour 2,593 · 7.8 mi | 44.7 | 23% | 1.2% | 0.8% |
| Auchel 10,051 · 8.2 mi | 40 | 20% | 0.5% | 1% |
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 Liettres
What is the population of Liettres?
378 at INSEE’s 2023 census, 28% more than in 2012 (296).
How old are Liettres’ residents?
The median age is 34.1, younger than 98% of compared French towns. 31% are under 18 and 8.9% 65 or older.
How many second homes are there in Liettres?
3, with occasional dwellings: 2.2% of all homes, against 2.1% for the median compared French town.
How many immigrants live in Liettres?
INSEE counts 0 immigrants (born abroad, not French at birth), 0% of residents, and 0 foreign nationals (0%). The medians of compared French towns are 6.5% and 4.3%.
What is the median income in Liettres?
€24,090 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 9, 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.