Convert any time between KST and BST, with a full 24-hour table and the hours when both sides are actually at work.

KST to BST Time Converter

BST is 8 hours behind KST. KST is UTC+9:00, and BST is UTC+1:00.

KST
Korea Standard Time
12:04:04 AM
Monday, October 12, 2026
UTC+9:00
-8:00
hours difference
⇆ Reverse
BST
British Summer Time
04:04:04 PM
Sunday, October 11, 2026
UTC+1:00

Best Time to Call Between KST and BST

Standard 9-to-5 hours in these two zones never overlap, so someone has to take the call outside their working day. The most workable window is 3:00 PM to 10:00 PM KST, which is 7:00 AM to 2:00 PM BST.

both at work KST only BST only neither  —  hours along the strip are KST.

KST to BST: Full 24-Hour Conversion Table

Shaded rows are working hours; the darker shade marks the hours when both zones are at work.

KSTBSTWorking hours
12:00 AM 4:00 PM prev day BST only
1:00 AM 5:00 PM prev day —
2:00 AM 6:00 PM prev day —
3:00 AM 7:00 PM prev day —
4:00 AM 8:00 PM prev day —
5:00 AM 9:00 PM prev day —
6:00 AM 10:00 PM prev day —
7:00 AM 11:00 PM prev day —
8:00 AM 12:00 AM —
9:00 AM 1:00 AM KST only
10:00 AM 2:00 AM KST only
11:00 AM 3:00 AM KST only
12:00 PM 4:00 AM KST only
1:00 PM 5:00 AM KST only
2:00 PM 6:00 AM KST only
3:00 PM 7:00 AM KST only
4:00 PM 8:00 AM KST only
5:00 PM 9:00 AM BST only
6:00 PM 10:00 AM BST only
7:00 PM 11:00 AM BST only
8:00 PM 12:00 PM BST only
9:00 PM 1:00 PM BST only
10:00 PM 2:00 PM BST only
11:00 PM 3:00 PM BST only

What KST and BST Actually Are

KST — Korea Standard Time

Seoul, Busan, Incheon. Standing at UTC+9:00 as written, and the region does not change its clocks, so that offset holds all year.

South Korea has used daylight saving only twice, most recently for the 1988 Seoul Olympics, and has kept a fixed offset since.

BST — British Summer Time

London, Manchester, Birmingham, Glasgow, and the rest of the UK from late March to late October. Standing at UTC+1:00 as written, and the region does change its clocks, so its live offset moves by an hour twice a year. The next change is on Sunday, October 25, 2026, to GMT. BST also stands for Bangladesh Standard Time (UTC+6). BDT is the clearer label for that one.

British Summer Time began in 1916 as a wartime fuel-saving measure and has run every year since, making it one of the oldest continuous daylight saving schemes in the world.

What This Means in Practice

This gap is not fixed

BST changes its clocks and KST does not, so the difference between them moves by an hour twice a year. A recurring meeting set now will drift for one side from Sunday, October 25, 2026 unless someone resets it.

Frequently Asked Questions

What is the time difference between KST and BST?

BST is 8 hours behind KST.

What is 9:00 AM KST in BST?

9:00 AM KST is 1:00 AM BST.

What are the best hours to schedule a call between KST and BST?

Standard business hours in these two zones do not overlap at all, so one side has to work outside the 9-to-5. The most workable window is 3:00 PM to 10:00 PM KST, which is 7:00 AM to 2:00 PM BST.

Does the difference between KST and BST change during the year?

Yes. BST observes daylight saving and KST does not, so the gap shifts by an hour at least twice a year. The next clock change is on Sunday, October 25, 2026.

Does BST always mean British Summer Time?

BST also stands for Bangladesh Standard Time (UTC+6). BDT is the clearer label for that one.

Converting between two time zones regularly? Bookmark this page — the clocks update live and the table follows daylight saving automatically.