International ~2–2.5 hours; domestic cabin-bag can work ~75–90 minutes off-peak; no civil night bank 23:00–06:00.

International departures want about 2–2.5 hours curb-to-gate on a normal Korea–Japan / Korea–China bank, and more when the new departure hall’s peak morning CIQ is stacked. Domestic cabin-bag passengers who already know the light-rail arrival can often work nearer 75–90 minutes when the hall is calm. Civil movements are noise-restricted 23:00–06:00 local — late inbound delays do not magically create a midnight departure bank.

Two buildings, free shuttle / short walk, no sterile domestic↔international transfer.

Read the boarding-pass terminal line before you commit to a lounge, meal, or light-rail exit. Domestic↔international same-day connections require a landside walk or free shuttle, re-check, and a second security / CIQ pass — there is no sterile link. The April 2024 international expansion added a second departure hall used heavily in peak morning banks (Air Busan emphasis); follow live FIDS and check-in zone signs, not a memorized 2019 blog map.

Landside CU and Korean food courts are the value play; airside is thinner and closes earlier than hub airports.

Landside CU convenience stores and the domestic food-court decks are the reliable everyday fuel — kimbap, noodles, fried chicken, coffee. Buy sealed water there before security. International airside adds duty-free and a thinner café set after passport control; useful once you are airside, poor value if you still have time landside. Most kitchens wind down in the evening — do not plan a sit-down dinner after a late curfew-edge arrival.

PP: Sky Hub / N Sky Hub / Air Busan; KE international is morning + metal restricted; domestic has no PP room.

Cardholders should open Priority Pass the same day. Default flexible rooms are Sky Hub (Gates 9–10, max 3h) and N Sky Hub (Gates 2–3, max 5h), both 06:30–21:30. Air Busan Lounge (3F, 06:00–22:00) is the strongest published paid/PP product and accepts other airlines’ walk-ups. Korean Air’s international lounge is PP-listed but only 07:00–13:00 and only on Korean Air / selected SkyTeam-operated flights — useless for an evening departure. Domestic passengers without Korean Air entitlement should use paid waiting rooms or the open hall, not PP.