Reader Question: I am self-employed as an auto-entrepreneur. I had to travel to another town to provide a service to a client. The client says he will reimburse the travel expenses, including hotel bill and meals. Can I just send him a facture [invoice] for these costs? How does this work for taxes?
The refund of costs that the client is offering should be included as part of your total sales, since they would be charged to the client.
Accordingly, yes, you need to send your client another facture for these costs, and then include this as part of your sales, though you will then be subject to the due social charges and tax on this amount.
If your client accepts this arrangement, since it is you who will be paying the tax and the social charges on these figures (and so in the end will not be refunded euro for euro), you might want to apply an enhancement coefficient to the total of these costs.
In this way, you will increase the amount your client pays, so as to possibly split the cost of the tax and social charges that you will pay between the two of you, so avoiding you being the only one to suffer the effects of the tax and the social charges