Do I invoice the traveller, or do you?

You do. You are the seller: the tour contract is between you and the traveller, and we are an intermediary that collects payment on your behalf.

The traveller receives a numbered payment receipt from us for what we charged their card. It names you as the seller, says we collected the money for you, and says it does not replace an invoice you have to issue yourself. It is proof that they paid, nothing more.

Card, through us: the receipt is for the whole price. A deposit, then you take the rest: the receipt is for the deposit alone, and says so. What passes between you and the traveller on the day is between the two of you.

Whether you have to issue your own invoice, and what it must look like, depends on where you are and how you are registered. Your accountant is the person to ask; we cannot answer it for you.