An information processing system includes a vehicle, and a server communicable with the vehicle. The vehicle includes a first acquisition unit configured to acquire first vital information on a user who boards the vehicle. The vehicle is configured to transmit to the server the first vital information on the user acquired with the first acquisition unit. The server is configured to prestore first vital information and settlement information on a registered user, determine whether or not the user is the registered user based on the first vital information on the user received from the vehicle and the first vital information on the registered user, and execute, when determining that the user is the registered user, a settlement process based on the settlement information on the registered user.