Bus (RATP)

The RATP operates the majority of buses in Paris and a significant number of lines in its suburbs. Other suburban lines are operated by private operators grouped in a consortium known as Optile (Organisation professionnelle des transports d'Île-de-France) an association of 80 private bus operators holding exclusive rights on their lines. There are approximately 4,000 buses serving the Paris region.

Bus services which are operated mainly in the city proper of Paris are named with two-digit numbers. Bus services which are operated mainly in the suburbs are named with three-digit numbers.

The RATP uses the numbers 20–96 for lines operated mainly in the city proper. The first number represents the terminal:

The second number represents the outermost arrondissement:

The RATP operates 63 bus lines within the city of Paris proper, and 214 bus lines in Paris suburbs. In 2014, 983 million journeys were made on RATP bus lines, including 330.7 million journeys on Paris lines and 652.3 million journeys on suburbs lines.

RATP also operate inter-urban services in some suburban communes:

Asnières (535)
Bondy (546)
Boulogne-Billancourt (571)
Cachan (581)
Choisy-le-Roi (582)
Clamart (579)
Clichy-la-Garenne (574)
Deuil-la-Barre (556)
Drancy (551)
Fontenay-sous-Bois (524)
Fresnes (583)
Gentilly (584)

Issy-les-Moulineaux (589)
Le Kremlin-Bicêtre (593)
Le Pré-Saint-Gervais (570)
Les Lilas (515)
L'Haÿ-les-Roses (592)
L'Île-Saint-Denis (578)
Malakoff (597)
Meudon (569)
Montrouge (526)
Nanterre (357)
Nanterre (559)

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Wikipedia