Three triggers.
The clock decides the rest.
Whichever of the Nifty 50 or the Sensex breaks the level first trips the entire market, either way.
| Index move |
Halt before 1 PM |
Halt later in the day |
| 10% | 45 min | 15 min . none after 2:30 PM |
| 15% | 1 hr 45 min | 45 min . rest of day after 2 PM |
| 20% | Rest of day | Rest of day |
When trading resumes it returns through a 15 min pre-open auction, not a normal open. Individual stocks have their own bands at 2 . 5 . 10 . 20%. The last index-wide halt was the open of 13 Mar 2020. A 45 min freeze.