Yes, Seoul and Tokyo are in the same timezone. Both cities use UTC+9 (KST and JST), so when it's 9:00 AM in Tokyo, it's also 9:00 AM in Seoul. Neither observes DST.
This makes business coordination between Korea and Japan straightforward with no time conversion needed.
Any time works! Since both cities share the same timezone, business hours align perfectly. Samsung in Seoul and Sony in Tokyo operate on the same clock.
Seoul and Tokyo are just 2 hours apart by air with Korean Air, Asiana, JAL, and ANA operating very frequent flights on this busy route.