How does billing work for members who use the service in both Ontario and Quebec?
Since your membership in Ontario or Quebec automatically gives you access to the other province, all charges will be billed to the credit card you have registered to your account.
(Please note, this is an exception. See: Can I use my Communauto membership in other provinces and countries?)
However, each branch operates independently for billing purposes. For this reason, if you are registered in Ontario, the daily charges for trips made in Quebec will not affect the balance of your Ontario account displayed in the Communauto app, and vice versa. You will need to wait for your monthly statement to see the details of these transactions. However, a confirmation email will be sent after each payment to notify you that a transaction has occurred.