If you cancel your flight, you'll receive a full refund if
You have 24 hours to Cancel a ticket that you bought straight from Delta Airlines.
There is a more than 90-minute cancellation or delay of your flight.
You are entitled to a complete refund under the terms of your fare.
a co-traveler on your reservation passes away.
You are a Delta Platinum or Diamond Medallion member and you have an award ticket.
You are unable to board your flight due to an unexpected military deployment order.
Any unusual circumstance keeps you from making your trip, and Delta agrees.