Metropolitan Pass (M-Pass), which had been limited to use on subway rides in the Seoul Metropolitan City area, can now be used on Seoul buses.
The M-Pass service has been expanded to provide international visitors with more options for public transportation operated in the metropolitan area.
The card types, prices and uses still remain the same. An M-Pass, available in five different types (1-day, 2-day, 3-day, 5-day, and 7-day), allows up to 20 rides on either a subway or a bus per day.
Courtesy of Ministry of Land, Transport and Maritime Affairs