A total of 360 trainsets have either been built or are under construction by Canadian conglomerate Bombardier at its Crespin, France (near Valenciennes) factory since 2006.

In 2004, the Syndicat des transports d'Île-de-France (STIF, the transit authority for the Paris region until June 2017) began the tendering process for approximately 180 new electric multiple unit trainsets to replace SNCF's aging single-deck suburban fleet, including trainsets nicknamed “inox” (short for inoxydable, English: stainless [steel]) (Classes Z 5300, Z 6100, Z 6400) and similar push-pull trainsets known as RIB (Rame inox de banlieue [fr]) and RIO (Rame inox omnibus [fr]).

The SNCF and STIF requested bids for a train design that could operate on a typical journey of 30 to 50 kilometres (19 to 31 miles) in length, including numerous stops lasting 30 to 40 seconds, and able to operate from either 1,500 V DC or 25 kV 50 Hz AC overhead catenary electrification.

[6] In 2006, SNCF (French Railway Company) and Syndicat des transports d'Île-de-France (STIF, the transit authority for the Paris region until June 2017) awarded the contract to Bombardier with a firm order for 172 ‘Francilien’ trainsets at a cost of €1.85 billion, with an option for 200 more.

[7] The first service operated by a Francilien train was on Transilien Line H from Paris Gare du Nord to Luzarches on Sunday 13 December 2009.

Total capacity exceeds 800 (or 1,000 in eight-car trains) including standing passengers at 4 per square metre (3.3/sq yd).

Each of these half-elements has two traction chains in parallel, redundancy which reduces the risk of unavailability in the event of a breakdown.