Can I Upgrade My Seat On Delta Online? According to the Delta seat upgrade policy, if your air ticket shows Upgrade Available, you can request the airline at the airport to upgrade your seat. Also, passengers can increase their service class once prior to their trip. You can request for a seat upgrade both online (via website) and offline (by phone). To know more about how I can upgrade my seat on Delta, dial +1-800-865-1848 (OTA get all your queries answered instantly. https://www.flyingrules.com/seat-upgrade/delta-airlines-seat-upgrade-policy