Objectives Aberrant driving behaviours among bus drivers cause serious concerns to safety on the road. The present study aimed to measure the effects of driver characteristics on aberrant and positive driving behaviours among bus drivers and to group drivers accordingly. The study was carried out among bus drivers of the government-owned road transport corporation in Kerala, India. Methods A total of 1120 drivers took part in the survey, out of which 617 drivers returned the forms with all questions answered (response rate = 55.1%). SPSS version 27.0 was used for analysis. Results Structural equation modelling proved the predictive nature of driver characteristics on driving behaviours. K-means cluster analysis revealed clusters such as violating and angry drivers (cluster 1), knowledgeable drivers with positive driving behaviours (cluster 2), healthy and stress-free drivers (cluster 3), erroneous and stressed drivers (cluster 4) and calm drivers with positive driving behaviours (cluster 5). Conclusion Positive relationships of anger and stress on aberrant driving behaviours and higher number of drivers in clusters 1 and 4 reveal concerns of safety. The study points towards the necessity of organizational commitment for improving driver characteristics for better driver behaviours and safer roads.