When's the best time to visit Seoul in 2026?

Seoul in October is a different city from Seoul in August. The summer's sticky heat — 33°C with 80% humidity, the kind that fogs your glasses stepping out of any GS25 convenience store — finally breaks around mid-September. By the second week of October the air turns dry and sharp, settling around 15–20°C during the day. You can smell roasted chestnuts from the vendors lining Insadong-gil, and the morning light hits Changdeokgung's Secret Garden at a low angle that turns the maple canopy copper and red. Bukhansan's granite ridgeline, invisible behind summer haze for months, suddenly appears from Gwanghwamun Plaza like it was always there. The trade-off: October is peak season. Hanok guesthouses in Bukchon book out weeks ahead, and weekend foot traffic on Samcheong-dong's narrow streets can rival rush hour on Line 2.

Spring is the other window, but it's tighter than people expect. Cherry blossoms along the Yeouido Hangang Park embankment last about ten days — usually the first week of April — and half of Seoul shows up with tripods and selfie sticks. The crowds are thick. That said, late April into May is underrated: the blossoms are gone but forsythia turns the hillsides above Naksan Park yellow, temperatures climb to 18–23°C, and you can walk the old Seoul City Wall trail past Ihwa Mural Village in a light jacket without breaking a sweat. Hotel rates sit about 20% below October levels. The catch: yellow dust blows in from the Gobi on some spring days, leaving a gritty film on everything and pushing air quality past 150 AQI. Pack a KF94 mask — they sell them at every pharmacy for about 1,500 won (~$1 USD).

July and August are the months to skip. The monsoon — called jangma — drops roughly 60% of Seoul's annual rainfall in about six weeks. Temperatures push past 30°C with humidity above 80%, and the combination is punishing. Myeongdong's shopping streets become rivers of umbrellas. The subway platforms at Jongno 3-ga smell like wet concrete and body heat. Outdoor markets like Namdaemun turn miserable by noon. Mind you, summer has one thing going for it: prices crater. A room at a mid-range hotel in Mapo or Hongdae that goes for 120,000 won (~$81 USD) in October might drop to 75,000 won (~$51 USD) in late July. If you handle heat well and plan mostly indoor days — museums, department store food halls, jjimjilbang — there are deals to chase.

Winter is polarizing. December through February drops to -5°C on average, and the wind cutting through Gwanghwamun intersection will find every gap in your coat. But Seoul does cold weather well: the ondol-heated floors of traditional hanok stays, the sizzle and steam rising from tteok-bokki carts in Sindang-dong Tteokbokki Town, the light displays strung between high-rises in Gangnam. Street vendors in Myeongdong sell hotteok — crispy pancakes filled with molten brown sugar and crushed seeds — and the warmth of one in your bare hands at -3°C is its own argument for the season. Crowd levels drop to their lowest all year. If you pack thermal layers and don't mind short daylight hours, January is a legitimate — and cheap — time to visit.