If scanning a validator upon boarding MARTA, an eligible prepaid ticket in your wallet will automatically be activated. However, you can manually activate your tickets before boarding the train, bus, or streetcar. If you are boarding a vehicle without being able to scan, you must manually activate your ticket. Bus operators will require an activated ticket. Please note that for single-trip tickets, once the ticket is activated, it will expire in 3 hours. For day passes, once the ticket is activated, it will expire at 2:00 A.M the following day.