Fare class SU is a revenue fare class that is used for cleared upgrade space into the Delta Comfort+ cabin on Delta Air Lines mainline and code share flights. This fare class is eligible for complimentary upgrades on domestic and short-haul international routes.

Also referred to as: Booking Class SU, Booking Code SU, Fare Class SU, Ticket Code SU, Class SU, SU Fare or Comfort (SU)

Delta Fare Class SU Frequently Asked Questions