Subprefecture and commune
|Coordinates: 48°50′07″N2°14′27″E / 48.83520°N 02.2409°E Coordinates: 48°50′07″N2°14′27″E / 48.83520°N 02.2409°E|
|Canton||Boulogne-Billancourt-1 and 2|
|• Mayor (2020–2026)||Pierre-Christophe Baguet  (LR)|
|6.17 km2 (2.38 sq mi)|
(Jan. 2019) 
|• Density||20,000/km2 (51,000/sq mi)|
|Time zone||UTC+01:00 (CET)|
|• Summer (DST)||UTC+02:00 (CEST)|
|Elevation||28–40 m (92–131 ft)|
|1 French Land Register data, which excludes lakes, ponds, glaciers > 1 km2 (0.386 sq mi or 247 acres) and river estuaries.|
Boulogne-Billancourt (French pronunciation: [bulɔɲ bijɑ̃kuʁ] ; often colloquially called simply Boulogne, until 1924 Boulogne-sur-Seine, [bulɔɲ syʁ sɛn] ) is a wealthy and prestigious commune in the western suburbs of Paris, France, located 8.2 km (5 mi) from the centre of Paris. It is a subprefecture of the Hauts-de-Seine department and thus the seat of the larger arrondissement of Boulogne-Billancourt. It is also part of the Métropole du Grand Paris. Boulogne-Billancourt includes two large islands in the Seine: Île Saint-Germain and Île Seguin. With a population of 121,334 as of 2018, it is the most populous commune in Hauts-de-Seine and most populous suburb of Paris, as well as one of the most densely populated municipalities in Europe.[ citation needed ]
Boulogne-Billancourt is one of the wealthiest regions in the Parisian area and in France.  Formerly an important industrial site, it has successfully reconverted into business services and is now home to major communication companies headquartered in the Val de Seine business district.
The original name of the commune was Boulogne-sur-Seine (meaning "Boulogne upon Seine").
Before the 14th century, Boulogne was a small village called Menuls-lès-Saint-Cloud (meaning "Menuls near Saint-Cloud"). In the beginning of the 14th century, King Philip IV of France ordered the building in Menuls-lès-Saint-Cloud of a church dedicated to the virgin of the sanctuary of Boulogne-sur-Mer, then a famous pilgrimage center in northern France. The church, meant to become a pilgrimage centre closer to Paris than the distant city of Boulogne-sur-Mer, was named Notre-Dame de Boulogne la Petite ("Our Lady of Boulogne the Minor"). Gradually, the village of Menuls-lès-Saint-Cloud became known as Boulogne-la-Petite, and later as Boulogne-sur-Seine.
In 1924, Boulogne-sur-Seine was officially renamed Boulogne-Billancourt to reflect the development of the industrial neighbourhood of Billancourt annexed in 1860.
As for the name Billancourt, it was recorded for the first time in 1150 as Bullencort, sometimes also spelled Bollencort. It comes from Medieval Latin cortem, accusative of cors, meaning "enclosure", "estate", suffixed to the Germanic patronym Buolo (meaning "friend, brother, kinsman"), thus having the meaning of "estate of Buolo".
On 1 January 1860, the City of Paris was enlarged by annexing neighbouring communes. On that occasion, the communes of Auteuil and Passy were disbanded and divided between Boulogne-Billancourt (then called Boulogne-sur-Seine) and the city of Paris. Boulogne-sur-Seine received a small part of the territory of Passy, and about half of the territory of Auteuil (including the area of Billancourt, which belonged to the disbanded commune of Auteuil).
Some of the shooting events of the 1900 Summer Olympics took place in Boulogne-Billancourt. 
In 1929, the Bois de Boulogne, which was hitherto divided between the communes of Boulogne-Billancourt and Neuilly-sur-Seine, was annexed in its entirety by the city of Paris. On that occasion, Boulogne-Billancourt, to which most of the Bois de Boulogne belonged, lost about half of its territory. Since then, Boulogne-Billancourt has been surrounded to the west, south and east by the Seine and to the north and north-east by the 16th arrondissement of Paris.
Boulogne-Billancourt is known for being the birthplace of three major French industries. It was the location, in 1906 for the very first aircraft factory, that of Appareils d'Aviation Les Frères Voisin,  which was then followed by those of many other aviation pioneers, and the tradition continues with several aviation related companies still operating in the area.
The automobile industry had a large presence with Renault on Île Seguin, as well as Salmson building both cars and aircraft engines. Finally, the French film industry started here and, from 1922 to 1992 it was the home of the Billancourt Studios, and since becoming a major location for French film production. It was used as the setting of the TV show Code Lyoko .
|Source: EHESS  and INSEE (1968-2017) |
With the city of Sèvres, Boulogne-Billancourt is part of the communauté d'agglomération Val de Seine.
Boulogne-Billancourt is served by two stations on Paris Métro Line 10: Boulogne–Jean Jaurès and Boulogne–Pont de Saint-Cloud. It is also served by three stations on Paris Métro Line 9: Marcel Sembat, Billancourt and Pont de Sèvres.
Boulogne-Billancourt is represented by two constituencies and therefore two Members of Parliament.
|Hauts-de-Seine's 9th constituency||Emmanuel Pellerin||La République En Marche!|
|Hauts-de-Seine's 10th constituency||Claire Guichard||La République En Marche!|
Boulogne-Billancourt hosts the global headquarters of several multinational companies, including:
Prior to 2000 Schneider Electric's head office was in Boulogne-Billancourt. 
The public collèges (middle schools) in the commune include Jacqueline-Auriol, Bartholdi, Paul-Landowski and Jean-Renoir. The public high schools are the Lycée Jacques-Prévert and the Lycée Polyvalent Étienne-Jules-Marey.  Prior to the September 1968 opening of Prévert, the first high school/sixth-form in Boulogne, an annex of Lycée La Fontaine served the city. 
The private school Groupe Scolaire Maïmonide Rambam covers maternelle through lycée. There is also the private high school Notre-Dame. The latter's performance and ranking in Boulogne-Billancourt are given by its success of baccalaureate rate in different series. According to the ranking of L'Express in 2015, the national rank of Notre-Dame de Boulogne was 170 out of 2301 and 7 out of 52 at department level. The private schools Dupanloup and Saint-Joseph-du-Parchamp serve maternelle through collège. Private maternelle and élémentaire schools include Saint-Alexandre and Saint-François d’Assise. Jardin de Solférino and La Maison de l'Enfant are private maternelles. 
The Association Eveil Japon (エベイユ学園 Ebeiyu Gakuen), a supplementary Japanese education programme, is located in Boulogne-Billancourt.  A campus of the École supérieure des sciences commerciales d'Angers is also located in the city.
Boulogne-Billancourt was the birthplace of:
Boulogne-Billancourt is twinned with: 
Hauts-de-Seine is a département in the Île-de-France region of France. It covers Paris's western inner suburbs. It is bordered by Paris, Seine-Saint-Denis and Val-de-Marne to the east, Val-d'Oise to the north, Yvelines to the west and Essonne to the south. With a population of 1,624,357 and a total area of 176 square kilometres, it is the second most highly densely populated department of France after Paris. It is the fifth most populous department in France. Its prefecture is Nanterre although Boulogne-Billancourt, one of its two subprefectures alongside Antony, has a larger population.
Neuilly-sur-Seine, also known simply as Neuilly, is a commune in the département of Hauts-de-Seine in France, just west of Paris. Immediately adjacent to the city, the area is composed of mostly select residential neighbourhoods, as well as many corporate headquarters and a handful of foreign embassies. It is the wealthiest and most expensive suburb of Paris.
The 16th arrondissement of Paris is the westernmost of the 20 arrondissements of the capital city of France. Located on the Right Bank, it is adjacent to the 17th and 7th arrondissements to the northeast, and to Boulogne-Billancourt to the southwest. Opposite the Seine are the 7th and 15th arrondissements.
Argenteuil is a commune in the northwestern suburbs of Paris, France. It is located 12.3 km (7.6 mi) from the center of Paris. Argenteuil is a sub-prefecture of the Val-d'Oise department, the seat of the arrondissement of Argenteuil. Argenteuil is part of the Métropole du Grand Paris.
Saint-Cloud is a commune in the western suburbs of Paris, France, 9.6 kilometres from the centre of Paris. Like other communes of Hauts-de-Seine such as Marnes-la-Coquette, Neuilly-sur-Seine and Vaucresson, Saint-Cloud is one of France's wealthiest towns, with the second-highest average household income of communities with 10,000 to 50,000 households. In 2019, it had a population of 30,012.
Montreuil, sometimes unofficially referred to as Montreuil-sous-Bois, is a commune in the eastern suburbs of Paris, France. It is located 6.6 km (4.1 mi) from the centre of Paris, in the Seine-Saint-Denis department and in the Métropole du Grand Paris. With a population of 111,367 as of 2020, Montreuil is the third most populous suburb of Paris after Boulogne-Billancourt and Saint-Denis. It is located north of Paris's Bois de Vincennes, on the border with Val-de-Marne.
Bondy is a commune in the northeastern suburbs of Paris, France. It is located 10.9 km (6.8 mi) from the centre of Paris, in the Seine-Saint-Denis department. In 2019, it had a population of 54,587.
Pierrefitte-sur-Seine is a commune in the Seine-Saint-Denis department and Île-de-France region of France. Today forming part of the northern suburbs of Paris, Pierrefitte lies 12.4 km (7.7 mi) from the centre of the French capital.
Croissy-sur-Seine is a commune in the Yvelines department in the Île-de-France region in north-central France. It is a suburban town on the western outskirts of Paris. Many expatriates reside in Croissy, given as it is the site of The British School of Paris, one of the top ten private international schools in the world.
Asnières-sur-Seine is a commune in the Hauts-de-Seine department and Île-de-France region of north-central France. It lies on the left bank of the river Seine, some eight kilometres from the centre of Paris in the north-western suburbs of the French capital. The inhabitants are called the Asniérois and the Asniéroises in French.
Levallois-Perret is a commune in the Hauts-de-Seine department and Île-de-France region of north-central France. It lies some 6 km (3.7 mi) from the centre of Paris in the north-western suburbs of the French capital. It is the most densely populated town in Europe and, together with neighbouring Neuilly-sur-Seine, one of the most expensive suburbs of Paris.
Ville-d'Avray is a commune in the western suburbs of Paris, France. It is located 11.9 km (7.4 mi) from the centre of Paris. The commune is part of the arrondissement of Boulogne-Billancourt in the Hauts-de-Seine department. In 2019, it had a population of 11,225.
Draveil is a commune in the department of Essonne in the southern suburbs of Paris, France. It is located 19.1 km (11.9 mi) from the center of Paris. It was formally twinned with Hove, East Sussex in The United Kingdom.
Maisons-Laffitte is a commune in the Yvelines department in the northern Île-de-France region of France. It is a part of the affluent outer suburbs of northwestern Paris, 18.2 km (11.3 mi) from its centre. In 2018, it had a population of 23,611.
Vaucresson is a commune in the western suburbs of Paris, France. It is in the Hauts-de-Seine department 13.9 kilometres (8.6 mi) from the center of Paris.
Villemomble is a commune in the eastern suburbs of Paris, France. It is located 12.1 km (7.5 mi) from the centre of Paris.
Longjumeau is a commune in the southern suburbs of Paris, France. It is located 18.2 km (11.3 mi) from the center of Paris.
Carrières-sur-Seine is a commune in the Yvelines department in the Île-de-France region in north-central France.
Saint-Denis is a commune in the northern suburbs of Paris, France. It is located 9.4 km (5.8 mi) from the centre of Paris. Saint-Denis is the second most populated suburb of Paris, with a population of 113,116 at the 2020 census. It is a subprefecture of the department of Seine-Saint-Denis, being the seat of the arrondissement of Saint-Denis. It is also part of the Métropole du Grand Paris.
Lycée Jacques Prévert is a senior high school/sixth-form college in Boulogne-Billancourt, Hauts-de-Seine, France, in the Paris metropolitan area.