The ASX is open for trading on weekdays, with the main trading session running from approximately 10:00 AM to 4:00 PM (Sydney time). Throughout the day, the market moves through several phases that affect your ability to place, amend, and fill orders. A summary of each phase is below.
| Phase | Time (Sydney) | What can I do? |
|---|---|---|
| Pre-Open | 7:00 AM – ~9:59 AM | Place, amend or cancel orders — no fills |
| Opening Auction (OSPA) | ~9:59 AM | Cancel orders only |
| Normal Trading | ~9:59:45 AM – 4:00 PM | Full trading — place, amend, cancel and fill |
| Pre-CSPA | 4:00 PM – 4:10 PM | Place, amend or cancel orders — no fills |
| Closing Auction (CSPA) | ~4:10 PM – ~4:11 PM | Cancel orders only |
| Post-Close | 4:11 PM – 4:21:30 PM | Trade at closing price only (eligible stocks) |
Times marked with ~ are randomised by the ASX and may vary by up to 15 seconds (OSPA) or 30 seconds (CSPA) either side of the listed time.
Pre-Open · 7:00 AM – ~9:59 AM
You can enter, amend, or cancel orders during this time. Orders are queued in order of price-time priority and will be held until the market opens.
Opening Single Price Auction (OSPA) · ~9:59 AM
Only order cancellations are permitted during this period — you cannot place or amend orders. If you wish to trade at market open, ensure your orders are placed during the Pre-Open period before 9:59 AM.
Tip: The OSPA start time is randomised and can occur up to 15 seconds either side of 9:59 AM. Place your orders during Pre-Open to avoid missing this window.
Normal Trading · ~9:59:45 AM – 4:00 PM
The market opens at approximately 9:59:45 AM. The opening price is calculated by the ASX at the start of this phase. During Normal Trading, orders can be placed, amended, cancelled, and filled — this is when the majority of trades take place.
Pre-CSPA · 4:00 PM – 4:10 PM
From 4:00 PM, the market enters the Pre-CSPA phase. Orders may be placed, amended, and cancelled during this time, but no orders will be filled.
Closing Single Price Auction (CSPA) · ~4:10 PM – ~4:11 PM
The closing price is calculated by the ASX at the start of this phase. The exact closing time is randomised and can occur up to 30 seconds either side of 4:10 PM.
Post-Close Trading Session · 4:11 PM – 4:21:30 PM
A Post-Close Trading Session runs immediately after the CSPA, from 4:11 PM to 4:21:30 PM. During this session, additional liquidity can be traded at the fixed closing auction price.
Please note: Post-Close Trading is only available for stocks that participate in the Closing Single Price Auction (CSPA).
The ASX typically closes on national public holidays. Visit the ASX calendars page (asx.com.au/about/calendars.htm) for the full schedule.
Further resources from the ASX
- Watch: Post-Close Trading Sessions explained
- Watch: Review of Opening Auction Changes