The trading curbs go into effect when the S&P 500 crosses certain thresholds during extreme market volatility.

Here's what to know about so-called “circuit breakers" and when they're used to halt trading on stock markets.

During heightened volatility, circuit breakers can be triggered to curtail panic selling and prevent an extreme downward spiral.

With the S&P 500 falling at this rate, the stock market could be at risk of triggering a circuit breaker.

Stocks fell sharply again Thursday, with declines nearing levels that would trigger a marketwide trading halt. These are the ...

Meanwhile, beyond the market-wide circuit breakers in place, there are also single stock circuit breakers. The single stock circuit breakers, or Limit Up-Limit Down (LULD) prevent extreme price ...

The Thursday selloff has torched more than $2.5 trillion in market value so far, but the stock market is still ways away from a trading halt. The S&P 500 was recently down 4.1%. It would need to fall ...

The S&P 500 was sinking fast, once again raising concerns it could trigger the New York Stock Exchange's market-wide circuit breakers. The S&P 500 was recently down 5.7% before paring its decline. If ...

The US stock market had a choppy first hour on Thursday with Dow Jones falling as much as 2,150 points, the S&P 500 and the ...

Asian stock markets took a huge plunge Monday as market sell-off tied to US President Donald Trump's "reciprocal" tariffs continued.