Find the exact window to book your Seoul flight for the lowest price — based on real long-haul pricing patterns, not guesswork.
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Seoul–Incheon (ICN) has extensive nonstop service from JFK, EWR, ORD, ATL, SFO, LAX, SEA, IAD, and DFW on Korean Air, Asiana, United, and Delta, with flight times around 14 hours — one of the best-connected Asian gateways from the US.
Spring (April–May, cherry blossoms) and fall (September–November, foliage) offer the best weather and are the most popular, most expensive seasons. Summer is hot, humid, and monsoon-prone (June–August); winter is cold but generally cheaper.
All the major carriers on this route are full-service — there's no dedicated long-haul low-cost operator flying nonstop to Seoul from the US, so booking within the optimal window matters more than choosing a specific airline.
6 to 8 weeks out on full-service carriers, or 5 to 7 weeks out on lower fare classes.
Winter (December–February) is generally cheapest. Spring (April–May) and fall (September–November) offer the best weather but are also the most popular and expensive.
No dedicated low-cost carrier flies nonstop to Seoul from the US — Korean Air, Asiana, United, and Delta are all full-service, so timing matters more than carrier choice.
US citizens need to register for South Korea's K-ETA (Korea Electronic Travel Authorization) online before departure, in addition to the visa-free short-stay allowance.