Why stock market's close is now an auction - explained

From August 3, 2026, the closing price of every stock in the F&O segment comes from an auction instead of a 30-minute average. Long-term investors need to do nothing. Traders, index funds and arbitrage funds have a new routine to learn.What changedFor over three decades, the closing price was the volume-weighted average (VWAP) of all trades between 3:00 pm and 3:30 pm. Nobody actually traded at that price. It was a calculation, not a transaction.Now, the roughly 200 stocks with futures and options stop normal trading at 3:15 pm and enter a Closing Auction Session. All buy and sell orders go into one pool. The exchange finds the single price at which the most shares can change hands, executes all matched orders at that price, and declares it the official close.