Roads pose a largely underestimated danger to companion animals, yet evidence shows that vehicle collisions involving dogs and cats are a significant and preventable risk to both animal welfare and human safety. We have conducted a national-scale analysis that demonstrates that these incidents cluster in densely populated coastal regions and peak during the late afternoon and nighttime hours, when reduced visibility and shifting traffic patterns increase vulnerability. Road design and environment strongly influence risk: higher speed limits, sinuous routes, and dense road networks elevate collision probability, while traffic signs, crossings, and speed control measures reduce it. Collisions occur more frequently in urban and agricultural areas, highlighting the interaction between free-roaming pets and human activity. Together, these findings emphasise that responsible pet ownership, combined with targeted road safety measures, can reduce collision risk and improve safety for both animals and people.