Heavy vehicle (HV) platooning promises economic and environmental benefits; however, this technology leads to highly clustered heavy traffic, which can significantly affect both vertical and horizontal loads on road bridges. This study assesses its impact on bridge braking forces. An existing probabilistic simulation model is updated to include braking events involving platooning. The objective is to estimate the change in braking forces relative to current traffic. The simulations are based on realistic traffic time-histories generated from road traffic counting stations and Weigh-In-Motion station data of the Swiss motorway network. Key parameters affecting the braking force, such as the number of heavy vehicles forming a platoon and the platoon penetration rate (percentage of HVs in a platoon configuration), are considered. The proposed stochastic modelling framework provides the value of the characteristic braking force for bridges of different lengths and dynamic characteristics, as a function of a given return period. The results highlight the significant impact of heavy vehicle platooning and show that the number of HVs in a platoon has the greatest impact on the maximum braking force, with the model indicating that in a four HV platoon, the braking force is almost double that of current traffic.