There is no overlap between 09:00–18:00 working days in these two places.
Clock changes in Boston and Seoul
Boston
Eastern Daylight Time (EDT)
Next clock change Sun 1 Nov 2026 (UTC−4 → UTC−5)
Seoul
Korean Standard Time (KST)
No daylight saving time.
Time difference between Boston and Seoul today
Right now Seoul is 13 hours ahead of Boston. When it is 09:00 in Boston, it is 22:00 in Seoul. Boston is on Eastern Daylight Time (EDT); Seoul is on Korean Standard Time (KST).
When the Boston to Seoul time difference changes
For most of the year Seoul is 13 hours ahead of Boston. From 1 November to 31 December 2026, Seoul is 14 hours ahead of Boston instead, because the two places change their clocks on different dates. Meetings booked by the usual gap land an hour off in those weeks.
Dates
Seoul vs Boston
Length
8 March 2026 to 31 October 2026
13 hours ahead
238 days
1 November 2026 to 31 December 2026
14 hours ahead
61 days
1 January 2027 to 13 March 2027
14 hours ahead
72 days
14 March 2027 to 6 November 2027
13 hours ahead
238 days
7 November 2027 to 31 December 2027
14 hours ahead
55 days
When Boston and Seoul are both at work
When Seoul is 13 hours ahead of Boston: no shared 09:00 to 17:00 hours; try 07:00 in Boston (20:00 in Seoul).
When Seoul is 14 hours ahead of Boston: no shared 09:00 to 17:00 hours; try 17:00 in Boston (07:00 in Seoul).
Frequently asked questions about Boston and Seoul time
What time is it in Seoul when it is 9:00 AM in Boston?
22:00 today; Seoul is 13 hours ahead of Boston.
Does the time difference between Boston and Seoul change?
Yes. It is usually 13 hours ahead, but changes when one side moves its clocks: 14 hours ahead from 1 November to 31 December 2026; 14 hours ahead from 1 January to 13 March 2027.