Tap off the bus: how Seoul's free transfer window actually works

Seoul's buses and subway run on one fare system, and the cheapest journey across the city often uses both. The saving rests on a single habit many visitors skip: tapping the card again on the way off the bus.

The second tap

Every Seoul bus has a card reader at the front door and another beside the rear door. Tap at both and the system records where you got off. Skip the second tap and the next ride is charged as a new journey. Subway gates make you tap out anyway, which is why the bus is where most transfers quietly disappear.

The window and the count

A transfer applies when you board the next vehicle within 30 minutes of tapping off the last one. Between 9pm and 7am the window stretches to an hour, a small concession to thinner night timetables. One journey can include up to four transfers, five rides in all, and the fare is worked out on the total distance rather than ride by ride.

Two exceptions catch people out. Boarding the same bus number again does not count, even in the opposite direction. And if the next ride carries a higher base fare, such as a red express bus to the satellite cities, the reader charges the difference.

What the reader tells you

The readers speak, and two phrases are worth knowing. A successful transfer is confirmed with 환승입니다 (hwanseung-imnida, "this is a transfer"). With two contactless cards in one wallet, you may hear 카드를 한 장만 대 주세요 (kadeureul han jangman dae juseyo, "please present only one card"), and the fare can land on the wrong one.

내리실 때 교통카드를 단말기에 대 주세요.

That line, naerisil ttae gyotongkadeureul dangmalgie dae juseyo, plays before stops on many routes: please touch your transport card to the reader when you get off. Treat it as part of the fare rather than a courtesy.