Roundtrip Flights from Seattle, WA (SEA) to Osaka, Japan (KIX) from $650 (Travel late-Aug to May, 2026)

Roundtrip Flights from Seattle, WA (SEA) to Osaka, Japan (KIX) for $650 (Travel late-Aug to May, 2026). United Airlines/ANA All Nippon Airways and Expedia have round trip airfares travelling from Seattle (SEA) to Osaka Japan (KIX) for $650-$660, making 1 stop both ways. Stopover airport and duration depends on the flight you choose. On United, there are flights that stop for a couple of hours in San Francisco and on ANA it will be in Tokyo for 5+ hours. These are basic economy fares that allow a personal item, a carry-on bag and 1 free checked bag. There is no seat selection and no change. If you are travelling with children, you will be seated together as per UA's policy.