KOSPI Circuit Breakers and Sidecars: Levels, Rules and Every Trigger
Start here · Guide 11 of 14
A KOSPI circuit breaker stops all trading in KOSPI stocks, and in the futures and options linked to them, for 20 minutes once the index has been 8% or more below the previous day’s close for one minute. Further stages apply at 15% and 20%, and the third stage ends trading for the day. A sidecar is a much lighter brake: it holds program orders for five minutes when KOSPI 200 futures move 5% up or down. KOSDAQ has the same three-stage circuit breaker and its own sidecar. Since the system began, circuit breakers have fired 16 times on KOSPI and 15 times on KOSDAQ, never beyond the first stage, and 15 of those 31 halts came in 2026, the latest on October 15.
In short
- Stage 1: the index is down 8% or more from the previous close for one minute. Trading stops for 20 minutes, then reopens with a 10-minute single-price auction. Stage 2 applies at 15% and stage 3 at 20%, which closes the market for the day.
- Each stage can fire only once a day. Stages 1 and 2 cannot fire in the last 40 minutes of the regular session (from 14:50 on a normal day), and nothing fires in the 16:00–20:00 after-market.
- A sidecar holds program buy orders (on a rally) or program sell orders (on a slump) for five minutes. Ordinary orders keep trading.
- 2026 is a record year: by October 15, KOSPI had 10 circuit breakers and 51 sidecars, and KOSDAQ had 5 circuit breakers and 33 sidecars.
- Nextrade, Korea’s alternative trading venue, halts the same stocks when KRX triggers a circuit breaker or sidecar. In 2026 it reopened exactly 30 minutes after each circuit breaker.
What is a circuit breaker in the Korean stock market?
A circuit breaker (CB) is a market-wide trading halt run by KRX (Korea Exchange). It works only on the way down; there is no circuit breaker for a sharp rise. KOSPI and KOSDAQ each have their own, measured on their own composite index, so one market can halt while the other keeps trading (see KOSPI vs KOSDAQ). KRX introduced the KOSPI circuit breaker on December 7, 1998; KOSDAQ’s first halt came in January 2006.
The test is always the index’s fall from the previous day’s close, and the fall must last a full minute. KRX can issue an advance notice when the index first crosses a threshold; the halt starts if it is still there a minute later.
| Stage | Trigger (index vs previous close, held for 1 minute) | What happens |
|---|---|---|
| Stage 1 | Down 8% or more | 20-minute halt in all stocks of that market and in linked stock futures and options, then a 10-minute single-price auction |
| Stage 2 | Down 15% or more, and at least 1% below the level where stage 1 fired | Another 20-minute halt and 10-minute auction |
| Stage 3 | Down 20% or more, and at least 1% below the level where stage 2 fired | Trading ends for the day; no new orders and no cancellations |
The extra 1% condition only matters when the market gaps down. If stage 1 fired with KOSPI already 14.5% lower, stage 2 would need a fall of about 15.4% rather than 15%.
What happens to orders during a halt?
During a stage 1 or 2 halt you cannot place new orders, but you can cancel orders already entered. On KOSPI the halt also covers the futures and options linked to the stock market (bond futures are not affected); on KOSDAQ it covers KOSDAQ 150 futures and single-stock futures. After 20 minutes KRX collects orders for 10 minutes, matches them at one price and then returns to continuous trading, so the market is effectively shut for about 30 minutes. At stage 3, order entry and cancellation both stop and the market does not reopen that day.
When can a circuit breaker not be triggered?
- Once per stage per day. A market can therefore halt at most three times in one session.
- Not near the close. Stages 1 and 2 cannot fire in the 40 minutes before the close, so that a closing price can be set. With the usual 15:30 close the cut-off is 14:50 KST. Stage 3 can still fire in that window.
- Regular session only. KRX says circuit breakers do not operate in its after-market, which has run from 16:00 to 20:00 KST since September 14, 2026.
- No grace period at the open. On June 8, 2026 KOSPI’s circuit breaker fired at 09:03.
The cut-off moves with the close when KRX changes its hours, as on the university entrance exam day. Our Korean stock market holidays guide lists the days when the market is closed or keeps different hours.
What is a sidecar on KOSPI and KOSDAQ?
A sidecar (officially a temporary suspension of program-trading orders) is a five-minute brake on computer-driven basket trading only. On KOSPI, “program trading” means index arbitrage between KOSPI 200 stocks and KOSPI 200 futures or options, plus any trade in which one investor buys or sells 15 or more KOSPI stocks at once; on KOSDAQ the basket threshold is 10 stocks. Individual orders, and the futures market itself, keep trading.
| KOSPI sidecar | KOSDAQ sidecar | |
|---|---|---|
| Trigger | KOSPI 200 futures 5% or more above or below their base price for 1 minute | KOSDAQ 150 futures 6% or more from their base price and the KOSDAQ 150 index 3% or more from its previous close, together for 1 minute |
| Effect | Program buy orders (buy-side) or program sell orders (sell-side) held for 5 minutes | Same |
| Limits | Once a day; not in the first 5 minutes or the last 40 minutes of the session; lifted if a circuit breaker halts the market | Same |
| Sessions | Regular session only | Regular session only |
The sidecar follows the direction of the move. A buy-side sidecar fires when futures jump and holds program buying; a sell-side sidecar fires when they drop and holds program selling. KOSPI’s sidecar dates from November 1996 and KOSDAQ’s from March 2001, and the current KOSPI trigger has applied since 2001. The US scrapped its own sidecar in 1999; after the record run of 2026, Korean market experts quoted in the press argued for raising the trigger or abolishing it, but as of mid-October 2026 KRX had announced no change.
How do circuit breakers differ from price limits and VI?
Korea layers four brakes, from the whole market down to a single stock. Circuit breakers and sidecars watch an index or index futures; the daily price limit and the volatility interruption (VI) watch each stock’s own price. Our market hours guide covers the stock-level rules in more detail.
| Measure | What it watches | Trigger | Effect |
|---|---|---|---|
| Circuit breaker | KOSPI or KOSDAQ composite index | -8%, -15%, -20% vs previous close, for 1 minute | Whole market and linked derivatives halted 20 minutes; stage 3 closes the market |
| Sidecar | KOSPI 200 futures (KOSDAQ: KOSDAQ 150 futures and index) | ±5% (KOSDAQ: ±6% and ±3%), for 1 minute | Program orders in that direction held 5 minutes |
| Daily price limit | Each stock | ±30% from its base price, usually the previous close | No trades beyond the limit |
| Volatility interruption | Each stock | Dynamic: a 3% (KOSPI 200 stocks) or 6% (others) jump from the last trade; static: 10% from the last auction price | That stock switches to a 2-minute single-price auction |
The index and stock rules have moved together. The KOSPI circuit breaker started on the same day, December 7, 1998, that the daily price limit was widened from 12% to 15%. When the limit was doubled to 30% on June 15, 2015, the single 10% circuit breaker was replaced by today’s three stages.
How does Nextrade handle circuit breakers and sidecars?
Nextrade (NXT), the alternative trading system that opened on March 4, 2025, has no index triggers of its own. It follows KRX: when KRX triggers a circuit breaker or sidecar, Nextrade applies the same measure to that market’s stocks.
- Circuit breakers: on October 15, 2026 Nextrade halted KOSDAQ stocks at 12:23:13 and KOSPI stocks at 12:38:12, each for 30 minutes, and reopened them at 12:53:13 and 13:08:12. All 15 halts in 2026 followed this pattern: Nextrade stays shut through KRX’s 20-minute halt and its 10-minute reopening auction.
- Reopening: since September 14, 2026 Nextrade collects orders for 30 seconds and runs a single-price auction before continuous trading resumes after a market-wide halt. Earlier in 2026 it went straight back to continuous trading.
- Sidecars: Nextrade also suspends program orders in the same direction for five minutes, as it did from 09:07:42 on October 15, 2026.
- Outside KRX hours: KRX’s circuit breakers and sidecars run only in its regular session. We found no separate market-wide halt for Nextrade’s 08:00–08:50 pre-market or for the evening sessions (Nextrade 15:40–20:00, KRX 16:00–20:00); there, only the ±30% price limits and stock-level VIs apply.
KOSPI and KOSDAQ circuit breaker history: every trigger
The table lists every market-wide circuit breaker from the start of the system to October 16, 2026: 16 on KOSPI and 15 on KOSDAQ. Before June 15, 2015 there was a single stage at a 10% fall, so the earlier halts needed a bigger drop. Times are KST; “fall at trigger” is the index’s decline from the previous close when the halt began.
| Date | Market | Stage | Trigger time | Fall at trigger | Close that day | Context |
|---|---|---|---|---|---|---|
| Apr 17, 2000 | KOSPI | Single (10%) | c. 09:04 | over 10% | 707.72 (-11.63%) | US stock market crash; first circuit breaker ever |
| Sep 18, 2000 | KOSPI | Single (10%) | 13:02 | 10.2% | 577.56 (-8.06%) | Surge in oil prices |
| Sep 12, 2001 | KOSPI | Single (10%) | c. 12:02 | over 10% | 475.60 (-12.02%) | September 11 attacks; the market opened three hours late |
| Jan 23, 2006 | KOSDAQ | Single (10%) | 14:19 | 10.2% | 601.33 (-9.62%) | US sell-off and collapse of theme stocks; first KOSDAQ circuit breaker |
| Aug 16, 2007 | KOSDAQ | Single (10%) | 13:20 | over 10% | 689.07 (-10.15%) | US subprime crisis spreads |
| Oct 23, 2008 | KOSDAQ | Single (10%) | 13:05 | 10.1% | 308.95 (-7.92%) | Global financial crisis |
| Oct 24, 2008 | KOSDAQ | Single (10%) | 13:16 | 10.1% | 276.68 (-10.45%) | Global financial crisis; KOSPI fell 10.57% but passed -10% too late in the day to halt |
| Aug 8, 2011 | KOSDAQ | Single (10%) | 13:10 | 10.4% | 462.69 (-6.63%) | S&P’s downgrade of the US credit rating |
| Aug 9, 2011 | KOSDAQ | Single (10%) | 10:41 | 10.2% | 432.88 (-6.44%) | Second straight day |
| Feb 12, 2016 | KOSDAQ | 1 | c. 11:55 | 8.2% | 608.45 (-6.06%) | Global recession fears; first halt under the 8% rule |
| Mar 13, 2020 | KOSDAQ | 1 | 09:04 | 8.3% | 524.00 (-7.01%) | COVID-19 crash |
| Mar 13, 2020 | KOSPI | 1 | 10:43 | 8.1% | 1,771.44 (-3.43%) | First KOSPI halt since 2001 |
| Mar 19, 2020 | KOSPI | 1 | 12:05 | 8.2% | 1,457.64 (-8.39%) | COVID-19 crash |
| Mar 19, 2020 | KOSDAQ | 1 | 12:05 | 8.3% | 428.35 (-11.71%) | COVID-19 crash |
| Aug 5, 2024 | KOSDAQ | 1 | 13:56 | 8.1% | 691.28 (-11.30%) | US recession fears |
| Aug 5, 2024 | KOSPI | 1 | 14:14 | 8.1% | 2,441.55 (-8.77%) | Same sell-off |
| Mar 4, 2026 | KOSDAQ | 1 | 11:16 | 8.1% | 978.44 (-14.00%) | US-Israeli strikes on Iran; fears of a long war and an oil shock |
| Mar 4, 2026 | KOSPI | 1 | 11:19 | 8.1% | 5,093.54 (-12.06%) | KOSPI’s biggest one-day percentage fall on record |
| Mar 9, 2026 | KOSPI | 1 | 10:31 | 8.1% | 5,251.87 (-5.96%) | Oil price spike from the Middle East war |
| Jun 8, 2026 | KOSPI | 1 | 09:03 | over 8% | 7,484.41 (-8.29%) | AI-profitability doubts and US rate-hike fears after strong May jobs data |
| Jun 8, 2026 | KOSDAQ | 1 | 14:36 | 8.0% | 911.39 (-9.08%) | Same day |
| Jun 23, 2026 | KOSPI | 1 | 14:33 | 8.1% | 8,203.84 (-9.99%) | Chip sell-off with heavy foreign selling |
| Jun 26, 2026 | KOSPI | 1 | 12:10 | 8.2% | 8,411.21 (-5.81%) | Memory-demand worries and profit-taking in chip stocks |
| Jul 7, 2026 | KOSPI | 1 | 13:51 | 8.1% | 7,656.31 (-4.91%) | Selling after Samsung’s preliminary Q2 results fell short of high hopes |
| Jul 13, 2026 | KOSPI | 1 | 13:28 | 8.1% | 6,806.93 (-8.95%) | Chip profit-taking after SK hynix’s ADR listing; new US-Iran strikes |
| Jul 28, 2026 | KOSPI | 1 | 10:13 | 8.0% | 6,023.66 (-10.84%) | US chip-stock plunge; Samsung Electronics and SK hynix sank |
| Jul 28, 2026 | KOSDAQ | 1 | 12:01 | 8.1% | 705.85 (-7.72%) | Same day |
| Jul 29, 2026 | KOSDAQ | 1 | 12:19 | 8.1% | 662.68 (-6.12%) | Second straight day |
| Jul 29, 2026 | KOSPI | 1 | 12:32 | 8.2% | 5,663.24 (-5.98%) | First time both markets halted on consecutive days |
| Oct 15, 2026 | KOSDAQ | 1 | 12:23 | 8.0% | 760.82 (-7.65%) | Hot US September inflation data and doubts over AI returns |
| Oct 15, 2026 | KOSPI | 1 | 12:38 | 8.0% | 5,554.22 (-7.57%) | Same day; intraday low 5,450.81 (-9.3%) |
“c.” marks a time that is approximate or comes from a single report. No circuit breaker fired in 2025: on April 7, 2025, when US tariffs hit markets, KOSPI fell 5.57% and only a sell-side sidecar was triggered.
What the record shows
- Stage 2 has never fired. The deepest close on a halt day was KOSDAQ’s 14.00% fall on March 4, 2026.
- Halts cluster in crises: 3 in 2000–2001, 6 on KOSDAQ in 2006–2011, 1 in 2016, 4 in March 2020, 2 in August 2024 and 15 in 2026. Both markets halted on the same day eight times, five of them in 2026.
- A halt does not mark the low or the close. On March 4, 2026 KOSPI kept falling after reopening and closed down 12.06%; on June 26 it recovered to close down 5.81%.
- The cut-off matters. On October 24, 2008 KOSPI closed 10.57% lower without a halt, because its fall passed 10% only after the cut-off then in force.
Why so many in 2026? KOSPI ended March 4 at 5,093.54, traded above 8,400 in late June and was back at 5,554.22 on October 15. Two chipmakers, Samsung Electronics and SK hynix, made up 46.9% of its market value on October 15 (author’s calculation from KRX data), so swings in chip stocks move the whole index. Our note on the October 15 KOSPI crash looks at that day in detail.
How often has the sidecar been triggered?
Sidecars fire far more often than circuit breakers because a 5% move in futures is easier to reach. Under the current rules, the busiest year before 2026 was 2008, the global financial crisis; KOSPI had no sidecar at all in 14 of the years since 2002. Years not shown had none on either market.
| Year | KOSPI sidecars | KOSDAQ sidecars |
|---|---|---|
| 2001 | n/a | 9 |
| 2002–2004 | 11 | 16 |
| 2005–2007 | 4 | 12 |
| 2008 | 26 (14 buy, 12 sell) | 19 |
| 2009 | 2 | 9 |
| 2011 | 5 | 2 |
| 2016–2019 | 0 | 5 |
| 2020 | 7 | 6 |
| 2023 | 0 | 2 |
| 2024 | 2 | 2 |
| 2025 | 3 | 2 |
| 2026 (to Oct 15) | 51 (24 buy, 27 sell) | 33 (18 buy, 15 sell) |
On February 3, 2026 KOSPI’s buy-side sidecar fired for the first time since April 10, 2025. Buy-side and sell-side sidecars then alternated through the spring rally and the summer sell-off, with 15 on KOSPI in July alone. After August 21, no sidecar fired on either market until October 13, 2026.
Is the Korean stock market halted today? Where to check
Nextrade posts every circuit breaker and sidecar, to the second, on its public market notice board (in Korean), and Korean brokers’ trading screens flag both in real time. In English, the Korea Herald, the Korea JoongAng Daily and the Korea Times cover each circuit breaker on the day.
For context after a sharp fall, our K-Expectation Index tracks Korean market sentiment, the foreign investor flows tracker shows whether foreigners were selling, and the KOSPI valuation tracker shows where P/E and P/B ended up. Short sellers often get the blame on crash days; the rules they work under, including the uptick rule, are in our short selling guide.
Frequently asked questions
How many times has the KOSPI circuit breaker been triggered?
Sixteen times since it was introduced on December 7, 1998, ten of them in 2026, the latest on October 15, 2026. KOSDAQ's circuit breaker has fired 15 times, five of them in 2026.
Has a stage 2 or stage 3 circuit breaker ever happened in Korea?
No. Every halt so far has been at the first stage (or, before June 15, 2015, the single 10% stage). The deepest close on a halt day was KOSDAQ's 14.00% fall on March 4, 2026, short of the 15% needed for stage 2.
What time did trading halt on October 15, 2026?
KOSDAQ's stage 1 circuit breaker fired at 12:23 KST and KOSPI's at 12:38, each halting trading for 20 minutes, after sell-side sidecars at 09:12 and 09:07. KOSPI closed down 7.57% at 5,554.22 and KOSDAQ down 7.65% at 760.82.
Can I still trade Korean stocks when a sidecar is triggered?
Yes. A sidecar only holds program orders in the direction of the move, such as index arbitrage or baskets of 15 or more KOSPI stocks, for five minutes. Ordinary buy and sell orders, and the futures market, keep trading.
Is there a circuit breaker when Korean stocks surge?
No. Circuit breakers apply only to falls. A sharp rally can trigger a buy-side sidecar, which holds program buying for five minutes, and each stock is still capped at a 30% daily rise.
Do circuit breakers apply in the 16:00-20:00 after-market?
No. KRX circuit breakers and sidecars operate only in the 09:00-15:30 regular session. When KRX does trigger one, Nextrade halts the affected stocks too.
Last reviewed: October 16, 2026.
Sources
- Circuit Breakers in stock market, Korea Exchange, accessed October 2026
- Program trading (sidecar for program trading), Korea Exchange, accessed October 2026
- KOSDAQ Circuit Breakers, Korea Exchange, accessed October 2026
- KOSDAQ Sidecar, Korea Exchange, accessed October 2026
- Daily Price Limits (historical changes), Korea Exchange, accessed October 2026
- Market notices: circuit breaker and sidecar notices, March 2025 to October 2026 (in Korean), Nextrade, accessed October 16, 2026
- Nextrade introduces static VI; single-price auction after halts (in Korean), MTN, August 31, 2026
- Kospi slides over 7% as chip stocks sink, The Korea Herald, October 15, 2026
- Circuit breakers by government since 1998: 31 in total (in Korean), NewDaily, October 15, 2026
- Kospi posts biggest drop ever at over 12% as Middle East instability spurs sell-off, Korea JoongAng Daily, March 4, 2026
- [DEBRIEFING] Of sidecars, uptick rules, circuit breakers and bans, Korea JoongAng Daily, March 30, 2020
- KOSPI and KOSDAQ plunge over 8%: second circuit breaker this year, The Asia Business Daily, March 19, 2020
- What are the sidecars and circuit breakers triggered on Black Monday? (in Korean), Metro Seoul, August 5, 2024
- Sidecar triggers by year, KOSPI and KOSDAQ (in Korean), The Korea Economic Daily via Nate News, August 19, 2026
- Do South Korea’s sidecars still serve purpose?, The Korea Herald, September 23, 2026
This guide explains how the Korean market works for general information. It is not investment, legal or tax advice; rules change, so check the official sources listed above or a qualified adviser before acting.