There are two terminals - domestic and international.
The two are about 5 minutes' walk apart, alternatively you can take the free airport bus between them.
The airport is very clear and the check-in process is extremely efficient.
For domestic departures, just arrive at the airport 40 minutes before departure, for international flights, allow 90 minutes instead.
Transfer between flights
Busan is not a major transfer hub, but it does have the option of transferring between flights without leaving the transit zone.
Signage is very clear and transfers are quick given the medium size of the airport.
- Domestic <-> Domestic: no controls, no need to leave the transit area
- Domestic <-> International: you have to exit the transit area, move to the other terminal and go through security and immigration
- International <-> Domestic: you have to go through immigration, pick up your baggage, exit the transit area, move to a second terminal and go through security
- International <-> International: security check, no need to leave the transit area