First decide whether you are airside or landside

If you are connecting between flights without entering Korea, follow the airport's transfer signs and airside transfer procedure. If you have cleared immigration, are checking in for a separate flight, meeting someone, or otherwise using the public area, use the landside terminal shuttle or another public transport option instead.

Landside: use the free terminal shuttle bus

Incheon Airport currently lists a free shuttle from Terminal 1 to Terminal 2 from 04:30 to 23:20, generally every 10–20 minutes, departing from Terminal 1's 3rd floor near Gate 8. In the other direction, the airport lists Terminal 2 to Terminal 1 service from 04:30 to 23:35, generally every 7–20 minutes, departing from Terminal 2's 3rd floor near Gate 7.

Allow extra time for the bus ride, waiting, elevators and check-in/security. Do not plan a tight terminal change around the last listed bus.

Airside transfer: follow the transfer route and shuttle train

For passengers remaining in the secure transfer flow, the airport's transfer instructions direct travelers through transfer security and a shuttle train between terminals. The shuttle train is listed at about five-minute intervals. The airport also warns that once you board the shuttle train you cannot simply reverse direction, so verify your terminal before boarding.

If you do not yet have a boarding pass for the onward flight, use the transfer desk instructions for your airline rather than leaving the transfer route by guesswork.

Accessibility

The airport lists a wheelchair-lift-equipped vehicle for terminal transfers from 05:00 to 24:00, with advance contact recommended because availability is limited. The airport lists 032-741-3217 for that service. General airport information is available at 1577-2600.

Before a tight connection

Confirm the operating terminal with the airline, then recheck the airport's transfer and shuttle pages on the travel day. Airline terminal assignments and transfer handling can change, and a landside connection requires enough time for immigration, baggage, check-in and security where applicable.