The Territoire de Belfort (; "Territory of Belfort") is a department in the northeastern French region of Bourgogne-Franche-Comté. In 2023, the population was 140,255. The department, which spans a relatively small surface area of 609.4 km<sup>2</sup> (235.3 sq mi), is situated just southwest of the European Collectivity of Alsace. It also shares a border with the Swiss canton of Jura to the southeast. Its prefecture is Belfort.
The administrative district of Territoire de Belfort was created under the terms of the 1871 Treaty of Frankfurt. The German Empire annexed almost all of Alsace. Still, the French were able to negotiate the retention of the Territoire de Belfort, which was thereby separated from the rest of Alsace (where it had been part of the department of Haut-Rhin). There were three principal reasons for this exceptional treatment:
After retaining its unique status as a for just over half a century, Belfort was officially recognized as France's 90th department in 1922. France had recovered Alsace three years earlier, but the decision was made not to reintegrate Belfort into its former department. There was talk of giving it a new departmental name, with suggestions that included "Savoureuse" (after the main river of the new department) or "Mont-Terrible" (the name of a former Napoleonic department embracing parts of Switzerland). Still, there was no consensus for a name change, and the department continues to be known as the Territoire de Belfort.
Belfort lies on the ridge that divides When the regions of France were created, Belfort was not included in the region of Alsace, but the adjacent region of Franche-Comté, since January 2016, Bourgogne-Franche-Comté.
The department has an area of only 609 km<sup>2</sup> (235 sq. miles), making it the fifth smallest of Metropolitan France (after Paris and its suburbs, Hauts-de-Seine, Seine-Saint-Denis, and Val-de-Marne). It is slightly smaller than Saint Lucia or Jakarta, Indonesia.
The most populous commune is Belfort, the prefecture, home to 33% of the department's population. As of 2023, there are 6 communes with more than 4,000 inhabitants:
The median net income per household for the department in 2017 was â¬21,310. The averaged figure for the Territoire de Belfort masked relatively large disparities, such as that between Belfort itself at â¬17,920 and Bermont at â¬26,600.
Four principal phases can be identified in the population trends during the two centuries between 1801 and 2000.
Its departmental code is 90, and its prefecture (capital) is Belfort. There is a single arrondissement (Belfort), which is subdivided into 9 cantons and thence into 101 communes.
The president of the Departmental Council is Florian Bouquet, first elected in 2015.