Asia's most competitive short-haul: 30+ daily departures across legacy and budget carriers from two Seoul.
Over 30 daily departures make ICN/GMP to NRT/HND one of the densest international corridors in Asia. Korean Air and Asiana serve both Incheon and Gimpo, while ANA and JAL focus on Narita and Haneda. Budget carriers t'way, Jin Air, Peach, and Jeju Air compete fiercely on price, sometimes dropping below KRW 50,000 one-way during fare wars. For Seoul - Tokyo, review carrier mix (Korean Air, ANA, JAL, t'way, Peach, Jin Air) before choosing a fare bundle.
The airport pairing matters enormously. Gimpo (GMP) to Haneda (HND) is the city-center-to-city-center champion: GMP is 20 minutes from Gangnam, HND is 25 minutes from Shinagawa. Incheon to Narita is the budget corridor but adds 2+ hours of ground travel at each end. Choose wisely based on where your hotel is. Seoul - Tokyo planning works best when transfer times and baggage rules are checked together.
Korean citizens enter Japan visa-free for up to 90 days. Complete Visit Japan Web registration before departure. Peak travel happens during Chuseok (Korean thanksgiving, September-October) and Golden Week (late April to early May) when fares and hotels in Tokyo spike 50+ percent. February and late June to early July are value sweet spots. When booking Seoul - Tokyo, benchmark this option against nearby alternatives for better value.
Gimpo to Haneda is best for central Seoul to central Tokyo trips: combined ground transfer is under 50 minutes. Incheon to Narita is cheaper but adds 2+ hours each way. For weekend trips, GMP-HND saves half a day.
During fare wars between t'way, Jin Air, and Peach, one-way tickets drop below KRW 50,000 (roughly $35). Legacy carriers rarely go below KRW 150,000 one-way but include baggage and meals.
No. Korean passport holders enter Japan visa-free for up to 90 days. Register on Visit Japan Web before departure for faster immigration processing.