Hello Community,
Effective December 8, 2025, both NSE and BSE are introducing a Pre-Open Session for the F&O segment . This change aligns the opening process of Futures contracts with the existing Equity segment.
While this is a regulatory change, we viewed it as an opportunity to upgrade our order handling systems. The result is a smoother experience with extended time windows for placing your After Market Orders (AMO).
Continuous Order Acceptance: No More Pauses
We have removed the system restrictions that used to block orders during specific market phases. Whether you trade Equity or F&O, you can now place orders continuously without worrying about rejection windows.
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First, we have extended the cut-off time. Previously, you had to stop placing AMOs for eligible Equity scrips by 8:58 AM. Starting December 8, you can place AMOs for all eligible scrips (both Equity and Futures) right up until 9:00 AM .
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Second, and perhaps most importantly, we have opened up the order matching window. Previously, if you tried to place an order between 9:08 AM and 9:15 AM, the system would reject it. Now, we will accept AMOs for all scrips during this time. These orders will be stored locally and automatically sent to the exchange when the market opens at 9:15 AM.
How Your Orders Will Behave
Since the Pre-Open session applies only to specific instruments, the system will handle your order differently depending on what you are trading.
For Eligible Scrips (Equity Shares and Current Month Futures ), orders placed between 9:00 AM and 9:08 AM are treated as Live Orders. They are sent to the exchange immediately to participate in price discovery.
For Non-Eligible Scrips (such as Options, ETFs, and Spread Contracts ), orders placed during that same time are treated as AMO. They are accepted, held locally, and fired at 9:15 AM.
Here is a quick look at how different scrips behave during the morning windows:
For a detailed breakdown of exactly how the new Pre-Open Session works for Futures contracts (including Equilibrium Price logic), you can read our previous update here: NSE’s Pre-Open Session for Futures: Live from 8 December .
Note for Upstox API (UDAPI) Users
If you use the Upstox API for algorithmic trading, please update your logic. Our system now automatically detects AMOs based on the timings and pre-open eligibilty. Even if you send an order with is_amo: true our backend system will override it.
You can view the full API announcement here: NSE Pre-Open Session API Update.
Community Discussion
With the ability to place orders during the 9:08–9:14 AM window now available, do you plan to use this time to react to the pre-open equilibrium prices, or will you wait for the 9:15 AM open?