South Korea and the United States share no working hours
South Korea and the United States have no hours where both are inside their own working day. South Korea works 09:00–18:00 and the United States 09:00–17:00, and the offset between them leaves no intersection.
Where this number comes from
South Korea works 09:00–18:00 and the United States 09:00–17:00, each on its own clock. The overlap is the intersection of those two days once both are put on the same axis .
On 1 November the difference between them moves by +1 hours. Neither country calls that a clock change of its own — one of them changes and the other does not, or they change on different dates — so a meeting fixed today is an hour out from then until the gap closes again.
The week on each side
South Korea works Monday, Tuesday, Wednesday, Thursday, Friday. the United States works Monday, Tuesday, Wednesday, Thursday, Friday. The weeks line up, so the only thing to get right is the hour.
What interrupts it in the next three months
A shared window is worth nothing on a day one side is closed. South Korea has 추석 (2026-09-24), 개천절 (2026-10-03), 개천절 (대체공휴일) (2026-10-05), 한글날 (2026-10-09). the United States has Columbus Day (2026-10-12), Veterans Day (2026-11-11), Thanksgiving Day (2026-11-26).
Who else you can reach
Sources and last check
Times, offsets and sun positions on this page are computed live from the IANA timezone database and the NOAA solar algorithm, so they do not depend on the review dates below.
- Working hours and weekend days for 55 countries
- Source: Published national labour conventions and government working-hours guidance. Last checked, reviewed every 12 months.
Not covered:A national convention, not any given employer. Countries not listed fall back to a nine-to-five, Monday to Friday default, and pages say so rather than implying we checked. - 141 countries: representative IANA zone and whether they observe DST
- Source: Generated by scripts/build-countries.mjs from Intl.DisplayNames and the tzdata shipped with Node. Nothing typed by hand.. Last checked, reviewed every 6 months.
Not covered:13 of them span more than one zone we hold; for those, `iana` is their largest city's zone rather than the whole country's.
FAQ
What is the best time to call the United States from South Korea?
There is no hour when both countries are at work. South Korea runs 09:00–18:00 and the United States 09:00–17:00; anything live means one side outside their working day.
Does the difference between South Korea and the United States change during the year?
Yes. On 1 November it moves by +1 hours, because the two countries change clocks on different dates — or one of them does not change at all. A standing meeting set today is that much out from that date until the other side catches up.