You purchased an economy plus or business class ticket, but on your return flight the plane is either oversold or the airline switches to a smaller aircraft and you are downgraded.

The airline owes you a refund, but the question becomes how the fare difference is calculated. In many cases, the airline applies the cost of a full-fare refundable coach ticket and then pays you the difference. As a result, you may receive far less money than you believe you deserve and you may be right.

The key is understanding that when you discuss the refund with the airline, the coach ticket price they apply against your refund amount is actually negotiable. It’s important to remind the airline that you did not voluntarily downgrade yourself.