Domestic Flights in Korea

In Korea, a domestic flight is worth it mainly for Jeju: Seoul’s Gimpo Airport to Jeju takes about 75 minutes, and nine airlines fly the route through the day. For Seoul to Busan the KTX train is the better choice, because it runs centre to centre. Foreign visitors show their passport at the gate. Since 20 April 2026, each passenger may carry at most two power banks, in hand luggage only, and may not charge with them on board. Fares, schedules and rules below were checked on airline and airport sites on 16 October 2026.

Your situation	What to do
Going from Seoul to Jeju	Fly from Gimpo, not Incheon; it is 22 minutes from Seoul Station by AREX
Going from Busan to Jeju	Fly from Gimhae Airport: about 1 hour, five airlines
Going from Seoul to Busan	Take the KTX (about 2 h 20 min, ₩54,400) rather than flying
Landing at Incheon and heading straight to Jeju	Take AREX to Gimpo (37–44 min) and fly from there; allow at least 3 hours for the transfer
Travelling with a big suitcase on a low-cost fare	Check the fare type: some cheapest fares include no checked bag

Which domestic routes are worth flying?

Korea’s mainland is well covered by fast trains, so most visitors fly only to and from Jeju. The three routes first-time visitors use most are below. Times are the scheduled gate-to-gate times in the Korea Airports Corporation (KAC) schedule for 20 October 2026.

Route	Scheduled time	Airlines (October 2026)	Better alternative?
Seoul Gimpo – Jeju	75 min (some flights 80–85)	Korean Air, Asiana, Jeju Air, Jin Air, Trinity Airways, Air Busan, Air Seoul, Eastar Jet, Parata Air	No: flying is the only practical way
Busan Gimhae – Jeju	60–65 min	Korean Air, Jeju Air, Jin Air, Air Busan, Eastar Jet	No
Seoul Gimpo – Busan Gimhae	65 min	Korean Air, Air Busan, Trinity Airways, Jeju Air	Yes: the KTX from Seoul Station

Gimpo–Jeju has flights from early morning to late evening. Some airlines on the list run only a few flights a day, so most of the choice of times comes from the larger carriers.

These lists come from the summer schedule, which ends on 24 October 2026. Airlines publish their winter timetables separately, so check the booking site for travel from late October.

Seoul to Busan: why the train usually wins

The flight itself is 65 minutes, but Gimpo and Gimhae both sit on the edge of their cities. Add the trips to both airports and the 30-minute check-in cut-off, and the journey takes about as long as the KTX, which runs from Seoul Station to Busan Station in about 2 h 20 min for ₩54,400. Korean Air’s regular Gimpo–Gimhae fare is ₩100,900 on weekdays. Fly only if a cheap fare turns up or you are staying near Gimpo.

Which airline should you choose?

All the airlines on these routes are Korean, and the flights are short, so the main differences are price and baggage.

• Full-service: Korean Air and Asiana. A checked bag of 20 kg is included, and the schedule is the widest. Asiana still flies and sells tickets under its own name.
• Low-cost: Jeju Air, Jin Air, Trinity Airways, Air Busan, Air Seoul, Eastar Jet, Parata Air. These are often cheaper, but the checked bag depends on the fare type you buy. Trinity Airways is the airline formerly called T’way Air, with the same TW flight codes.

How much does a domestic flight cost?

Korean fares are quoted as a total that already includes the fuel surcharge and the airport usage fee. Korean Air publishes its regular economy fares in a monthly fare table. The October 2026 one-way fares are below.

Route	Weekday (Mon–Thu)	Weekend (Fri–Sun)	Peak days
Gimpo – Jeju	₩106,900–110,900	₩119,900–124,900	₩141,900
Gimhae – Jeju	₩88,900–94,900	₩97,900–103,900	₩114,900
Gimpo – Gimhae	₩100,900	₩112,900	₩122,900

• Why two prices: the higher figure is for “preferred” times, which means flights to Jeju before 15:00 and flights from Jeju from 12:00.
• Busy days: Korean Air applies its peak price to Jeju-bound flights on Fridays and Saturday mornings, and to flights from Jeju on Sunday afternoons. Peak dates in late 2026 include 24–25 and 31 December.
• What is included: the fuel surcharge of ₩20,900 one way applies to tickets issued in October 2026 and can change each month. The ₩4,000 domestic airport usage fee is the same at every airport KAC runs. Children aged 2–12 pay half the airport fee, and infants under 2 pay none.
• Cheaper fares: these are Korean Air’s regular fares. Its discount fares and the low-cost airlines’ fares are often well below them, especially on weekdays, but they change daily and are not published in a table. Compare a few airlines for your date.

How to book and check in

1. Book on the airline’s own site or app. Korean Air, Asiana and Jeju Air have English sites. Trinity Airways states that it accepts overseas Visa, Mastercard and JCB cards, with a 3D Secure check.
2. Enter your name exactly as in your passport. It is checked against your ID at the gate.
3. Check in online or at the airport. With hand luggage only, mobile check-in lets you go straight to security. With a bag, use the airline’s counter or bag-drop.
4. Be at the airport 1 to 2 hours before departure. Airlines advise different times, but every airline below closes its check-in counter 30 minutes before departure.
5. Show your passport and boarding pass at the entrance to the departure area, then go through security to the gate.

Each airline sets its own deadlines. These are the times on each airline’s own pages:

Airline	Check-in counter closes	Boarding gate closes
Korean Air	30 min before departure	10 min before (boarding from 20 min)
Asiana	30 min before	5 min before (boarding from 15 min)
Jeju Air	30 min before	Not stated
Jin Air	30 min before	5 min before
Trinity Airways	30 min before	10 min before (boarding from 20 min)

Jin Air adds that passengers who are not inside the departure area 30 minutes before departure may be refused boarding. Treat 30 minutes as the real deadline on every airline.

How much baggage can you take?

Free baggage for economy passengers on domestic routes, from each airline’s baggage pages (checked 16 October 2026):

Airline	Free checked bag	Hand luggage
Korean Air	20 kg	1 bag (55 × 40 × 20 cm) plus 1 small item, 10 kg in total
Asiana	20 kg	1 bag (115 cm in total) plus 1 small item, 10 kg in total
Jeju Air	15 kg on Standard fares, 30 kg on Biz Lite, none on Basic	Bag plus small item, 10 kg in total
Jin Air	15 kg	1 bag of 10 kg (12 kg on flights between Jeju and Gimpo, Cheongju, Gwangju or Busan) plus a laptop bag or handbag
Trinity Airways	20 kg on regular fares, 15 kg on Smart fares, none on event fares	Bag plus small item, 10 kg in total

On the low-cost airlines the cheapest fare often has no checked bag, so add one when you book if you need it. A full-size suitcase is usually over 15 kg by the end of a trip, so check the weight before you choose a fare.

What you need at the airport

Your passport

Every passenger shows photo ID with their boarding pass before security. Foreign visitors should carry their passport itself: Incheon Airport’s list of accepted ID rules out expired documents, photocopies, photos and screenshots. Residents can use an alien registration card instead.

Gimpo and Jeju have fast lanes for passengers who have registered biometric ID, but KAC limits that registration to Korean nationals. Korean mobile IDs are for Korean-issued cards, so tourists use the normal lane with a passport.

Power banks: the 2026 rules

The transport ministry tightened the rules for power banks on all flights from 20 April 2026, in line with a new international standard:

• No more than two power banks per person, each 160 Wh (43,000 mAh) or less. Before April 2026 the domestic limit was five.
• No charging on board: you may not charge the power bank, or plug your phone or another device into it.
• Hand luggage only: never in a checked bag. Asiana also asks you to keep them on you or in the seat pocket, not in the overhead bin.
• Cover the terminals with tape, a cap or a small zip bag so they cannot short-circuit. Asiana’s notice adds that spare lithium batteries of 100–160 Wh need the airline’s approval.

Liquids are not limited on domestic flights

Korea’s 100 ml rule for liquids applies to international and transfer flights only. A full bottle of water or sunscreen can go through security on a flight from Gimpo or Jeju. Dangerous goods such as fuel, bleach and pesticides are banned on all flights. If you connect to an international flight on the same ticket, the 100 ml rule applies.

Getting to Gimpo Airport

Gimpo is Seoul’s domestic airport, west of the city centre. The subway station is under the airport, served by the AREX airport railway, subway lines 5 and 9, the Gimpo Goldline and the Seohae line.

• From Seoul Station: the AREX all-stop train takes 22 minutes and costs ₩1,750 by transport card, from 05:20 to midnight. A T-money card works on every line to the airport.
• From Incheon Airport: the AREX all-stop train takes 37 minutes from Terminal 1 (₩4,350 by card) and 44 minutes from Terminal 2 (₩4,950). With the walk to the domestic terminal and the 30-minute cut-off, allow at least 3 hours between landing at Incheon and a flight from Gimpo.
• Domestic and international terminals are separate buildings. For a domestic flight, head for the domestic terminal. A free shuttle bus links the two terminals from 08:00 to 23:00, every 12–15 minutes.

From Busan, Gimhae Airport is on the city’s western edge, near the Nakdong River. Allow extra time if you are coming from Haeundae or the east of the city.

Arriving at Jeju Airport

Jeju International Airport is on the edge of Jeju City, so hotels in the city are a short taxi or bus ride away. For Jungmun and Seogwipo on the south coast, airport limousine bus 600 leaves from the stop in front of Gate 5, from 06:00 to 22:40. Express and local island buses leave from the stops along the arrivals hall. For buses, rental cars and where to stay, see the Jeju guide.

What can go wrong

Where to next

For the mainland, compare KTX trains and express buses, or start with the transportation overview. The Jeju guide covers Hallasan, Seongsan Ilchulbong and getting around the island. The 10-day Korea itinerary shows how a Busan–Jeju flight and a Jeju–Gimpo return fit into one trip.