Paying for a night bus from Incheon Airport: card or cash?

Are there night services at all?

Yes, and they are numbered so you can recognise them. N6002 is the night counterpart of route 6002 between Incheon Airport and Hongdae, so the N prefix is how that night service is distinguished from its daytime route.

Can I just tap a foreign card when I board?

Not on the bus. 공항리무진 (Airport Limousine bus) is explicit: No. That is documented for journeys towards the airport, where you pay the driver; the practical consequence at night is the same in both directions, because the alternative is a ticket bought before you board.

What the driver does take, going towards the airport, is narrow: Towards the airport: cash or a transportation card (T-money) paid to the driver. Credit cards cannot be processed on the bus..

So how do I pay leaving the airport at 1am?

With a ticket bought in the terminal. Towards the city: buy a ticket at the staffed booth or the vending machine at the airport before boarding. Ticket holders board first, including on late-night buses.

And the priority rule explicitly covers night services: Ticket holders board first, and this includes late-night buses. On a thin late-night timetable, missing a departure because someone with a ticket took the last seat is a long wait, not a short one.

Where do I buy it at that hour?

At 인천국제공항 (Incheon International Airport) Terminal 1 the booths are spread along the exits: Terminal 1 bus ticket booths are inside the terminal next to exits 4 and 9, and outside near exits 4, 6, 7, 8, 11 and 13. At Terminal 2 the counter and machine are elsewhere in the building: Terminal 2: ticket counter or ticket vending machine in Basement 1. Terminal 1: ground floor..

There is one narrow exception at Terminal 1 only: Routes 6001, 6002 and 6015 at Terminal 1 only are first-come, first-served, and accept cash, a transportation card or a ticket. If your route is one of those three and you are at Terminal 1, cash or a transit card at the door will work.

What if I have no won and no transit card?

Sort the payment before you leave the arrivals hall. A 티머니 (T-money transit card) card is the general-purpose answer: Bought at convenience stores nationwide, then registered on the T-money Card & Pay website, and airport convenience stores sell them.

If you need help and the counters look closed, the airport's general line is 1577-2600 — but note the staffed hours are 07:00–22:00, which is exactly the window a 1am arrival falls outside. Plan on the machines and the store, not on a phone call.