The Paris-Lyon line is the busiest High-Speed Line in Europe and has been open to competition in open access since December 18, 2021. The main objective of the paper is to explore the effects for users with respect to price and frequency compare with the existing literature. The analysis is based on a large database (n = 1243) collected by web scraping from September 2019 to October 2022. The method relies on a descriptive analysis with a similar route without competition (Paris-Bordeaux) in the comparison group. The results highlight an increase of frequency by 15% and a decrease in price by 23%. The prices charged by the newcomer are lower than those of the incumbent (−30% to −50%). The comparison with the control route suggests a positive effect on price that moderates the economic catch-up effect following the COVID-19 pandemic in an inflationary context. More specifically, SNCF appears to take a wait and see attitude to competitive pressure from Trenitalia. It has moderated its prices since the new offer was introduced and has maintained its trains.