Yes, the passenger details for each person travelling on every booking must be supplied.
We have recently revised our system so that all travellers have the option to store API for future use when you add a set of passenger details.
See our how-to guides for more information
Please note we only require your API information for the Folkestone to Calais part of your journey. We do not require API information for the Calais to Folkestone part of a return trip, or trips that are Calais to Folkestone only.