Alongside the fleet renovation, OUIGO plans to expand its network. From December 2025, a new daily service will connect Paris to Hendaye, via Dax, Bayonne, Biarritz, and Saint-Jean-de-Luz. This extension towards the southwest will add another daily connection to Bordeaux as part of the same operation.

On the Paris–Rennes line, a third OUIGO high-speed round-trip will be introduced from December 2025, supplementing the existing two daily services. An additional third round-trip on the Paris–Rennes route using OUIGO Train Classique is scheduled to start on 12 May 2025.

The Paris–Montpellier service via Lyon Saint-Exupéry will see the addition of a third daily high-speed round-trip during the summer of 2026. Furthermore, the Paris–Lyon high-speed link, which currently operates two daily round-trips, will add a third round-trip during weekends starting in December 2026.