This study estimates the price effects of horizontal mergers in the French long-distance bus industry. We examine the two mergers that followed the 2015 Deregu-lation Act in theMacron Law. Using an exclusive and exhaustive database coveringeight consecutive quarters, we identify price effects by comparing those bus routesaffected by mergers to those that were unaffected using difference-in-differences (DiD)estimations with propensity score matching. We provide two alternative counterfac-tuals to test the robustness of our results. We find that the two mergers following thederegulation seem to be associated with price increases. In the first quarter followingthe acquisitions, price increases were about betweene0.40 ande0.65/100km, i.e. aroughly 10% price increase. However, those increases are diminishing over time, andfor alternative counterfactual scenarios vanish totally by the last quarter observed