i think the point is most employers I knoof would not see it as the company’s role to sponsor the « happy wife » part. I think many companies have reasonable elements of tolerance - eg if work is paying for the hotel room anyway and there is no surcharge for a second person in the room then they won’t mind that a partner free rides on that at no additional cost to the company, or if you go somewhere for work then decide to take the weekend off as holiday and pay for your own accommodation etc most will let you book your return date accordingly and not make you split the cost of the plane ticket or whatever. This, however, is an entirely scenario. You are effectively make the company pay the business class trip of a non employee on a non company related trip whilst the employee surrenders what the company considers is the travel conditions necessary for the performance of their job but not the cost associated with it. It’s one of those cases where nobody may ever find out but if you ever have « enemies within », it offers them ammunition on a silver platter to make one’s life miserable. Anyway, perhaps more importantly, there are lots of threads on the swap question and some on the swap question for business travel so maybe best do a little search for advice and experience .