What it is
Circuit breakers pause the entire market after a steep index drop to give investors time to cool off.
Triggers
If KOSPI (or KOSDAQ) falls 8% or more from the prior close for one minute, trading halts for 20 minutes (stage 1). At 15% another 20-minute halt follows (stage 2); at 20% trading ends for the day (stage 3). Each stage triggers once a day, and stages 1 and 2 do not trigger after 14:50.
What to keep in mind
KOSPI circuit breakers have fired after the September 11 attacks in 2001, during the March 2020 COVID-19 crash and in the August 2024 sell-off, among others. They differ from the sidecar, which only pauses program trading.
This explanation is general information, not investment advice. Rules reflect September 2026 and may change; check official exchange and broker notices.