The train was designed and originally built by Bombardier, but during delivery the company was bought by Alstom, which completed the order.

The Omneo had been designed by Bombardier's facility at Crespin in response to a request issued by SNCF, which had sought to equip itself with a new generation of regional EMUs.

Following the receipt of several bids, during November 2009, an SNCF spokesperson stated that Bombardier was the preferred bidder at that stage.

In September 2013, a ceremony was held at the Crespin manufacturing plant, where Bombardier build the Omneo, at which the first trainset was delivered to SNCF; it was attended by company president Guillaume Pepy and various representatives of the regions that had funded the order—by that time expanded to 129 trainsets—ahead of delivery and testing across SNCF's own network.

It features a modular design approach, allowing the trainset to be readily adapted for suburban, regional and intercity traffic.

[12] It has been anticipated that a common intercity configuration would feature a 2+1 seating configuration, dedicated luggage spaces, increased toilet capacity, greater seat pitch, individual reading lights and electric sockets, and footrests for greater comfort.

The Premium variant of the Omneo features various improvements in passenger amenities over the Base model, these include spacious reclining seats with individual armrests, wider doors and a more luxurious interior.

[14] The trainsets are composed of relatively lightweight materials, which minimises axle loads; the Omneo is claimed by Bombardier to be 95% recyclable.

[12] Due to its high level of French-sourced content, the Omneo has received a Guaranteed French Origin label, the first to be granted within the rail industry.