An authorized user means that you're using a card that's billed to someone else. For example, if I use my employer's card to buy lunch for a client, my employer is responsible for paying the bill not me. However, if you're using your spouse's card or a friend's card with the understanding that you'll pay for the charges, then you're incurring debt and that's prohibited.
Answered on Sep 29th, 2017 at 8:14 AM