NSE Pre-Open Market

Ans. The NSE pre-open market is a 15-minute session (9:00–9:15 AM) before regular trading starts. It allows traders to place orders for Nifty 50 stocks. NSE uses these orders to determine a fair opening price — called the IEP (Indicative Equilibrium Price) — which becomes the opening price for regular trading at 9:15 AM.

Ans. The pre-open session runs from 9:00 AM to 9:15 AM, Monday to Friday (on trading days). It has three phases: Order Entry (9:00–9:08 AM), Order Matching (9:08–9:12 AM), and Buffer/Transition (9:12–9:15 AM). Regular trading begins at 9:15 AM sharp.

Ans. Only Nifty 50 stocks are eligible for pre-open trading. Additionally, stocks that are newly listed (IPO Day 1 and Day 2) can also be traded in the pre-open session. Mid-cap, small-cap, and other stocks are not eligible.

Ans. IEP stands for Indicative Equilibrium Price. It is the price at which the maximum number of buy and sell orders can be matched from all the orders placed during the pre-open session. NSE calculates and publishes this price during the 9:08–9:12 AM matching phase. The IEP is the likely opening price when regular trading begins at 9:15 AM — though it can change slightly if unmatched orders shift the price.

Ans. Yes — but only during the Order Entry phase (9:00–9:08 AM). Once the matching phase begins at 9:08 AM, you cannot modify or cancel orders. If your order is not matched during the pre-open session, it carries forward to the regular trading session (if it's a Limit order at an unmatched price).