Saint-Denis Population and Area (Seine-Saint-Denis)
Largest city in France 2026: up-to-date figures for Saint-Denis (Seine-Saint-Denis)
Saint-Denis: Population and Area
With 149,936 inhabitants (INSEE total population in force on January 1, 2026), Saint-Denis is the 23rd most populous town in France in 2026 and the most populous in the Seine-Saint-Denis department, out of 39 communes. It covers 16 km² (11,375th largest area in France, 3rd largest in the department), with a population density of 9,508 inhabitants per km², or 87 times the national average (110 inhabitants/km²), which ranks it 47th in France for density.
Saint-Denis is located in the Seine-Saint-Denis department (93), in the Île-de-France region, where it ranks 2nd by population out of 1,266 communes. It is the most populous town in the Seine-Saint-Denis department, which is home to 1,710,659 people over 236 km².
See the full ranking of communes in the Seine-Saint-Denis department and the regional ranking: largest city in Île-de-France.
Towns of similar size in the Seine-Saint-Denis department: Montreuil (pop. 112,549), Aubervilliers (pop. 88,529), Aulnay-sous-Bois (pop. 87,951).
Sources: INSEE, official population figures in force on January 1, 2026 (total population); areas: IGN / Observatoire des territoires; INSEE code 93066. Rankings are calculated across the 34,858 communes of metropolitan and overseas France in our database.
Saint-Denis, the largest city in Île-de-France after Paris
Since January 1, 2025, and its merger with Pierrefitte-sur-Seine, Saint-Denis has been the second-largest town in Île-de-France, ahead of Boulogne-Billancourt and Montreuil. A subprefecture of the Seine-Saint-Denis department bordering northern Paris, the city first grew up around its basilica, the burial place of the kings of France, then with the 19th-century factories that made it one of the great working-class towns of the Paris suburbs.
Growth among the strongest in France
After the industrial crisis of the 1970s and 1980s, Saint-Denis bounced back around the Stade de France, the corporate headquarters of La Plaine Saint-Denis and the facilities of the 2024 Olympic Games, including the athletes' village. For twenty years it has posted one of the strongest population growth rates in Île-de-France, with a young and very dense population: on a small territory, the city houses more people than many provincial prefectures ten times its size.