ASX Service Release 15 (SR15) represents a significant milestone for the market, delivering a program of market structure upgrades designed to enhance the efficiency and resilience of the Australian market while aligning with international standards.
Why these changes matter
Today’s market environment demands speed, reliability, and the ability to adapt to changing regulations. Exchanges seeking to remain competitive need infrastructure that not only delivers low-latency and efficient trade execution but also stability and compliance under ever-evolving market pressures. SR15 responds to these requirements by enhancing the ASX’s trading systems through streamlining processes and strengthening the resilience of the Australian market.
Key updates introduced by SR15
A central element of SR15 is the shift to a unified Opening Single Price Auction (OSPA), replacing the staggered opening auction that divided securities into groups opening sequentially. The OSPA introduces a randomised 15-second window starting at 09:59:00, followed by a 30 to 60-second window for auction execution. This reduces fragmentation, enhances price discovery and aligns the ASX with major global exchanges like the NYSE, LSE and NASDAQ.
SR15 also introduces a new 10-minute post-close session that allows lit-order trading at the official closing price. This mirrors practices on other global exchanges and increases post-close liquidity, offering investors greater flexibility for end-of-day trading and rebalancing. Additionally, securities with late-breaking announcements can now participate in the closing auction, ensuring material information is reflected in the closing price and supporting fairer price formation.
Industry collaboration to ensure a smooth transition
An upgrade of this scale requires coordinated industry-wide readiness. Since the announcement of SR15 in 2024, Iress has worked closely with clients, brokers, custodians, and the broader industry to ensure all participants were prepared. This included detailed migration planning, rigorous testing and software updates to minimise disruption and maintain operational integrity.
On the first day of SR15’s operation, the ASX operated smoothly, demonstrating market confidence in the transition. Orders and trades processed via Iress maintained high-performance standards, ensuring operational workflows remained uninterrupted.
Looking ahead
SR15 positions the ASX to remain a modern, competitive, and investor-friendly exchange while supporting the evolving needs of the Australian financial market. For market participants, the upgrade offers an opportunity to review processes, reduce operational risk, and enhance their ability to engage confidently with the market.
At Iress, we are committed to supporting clients through these changes, ensuring systems and workflows are optimised for performance in the new environment. As global markets continue to evolve, staying prepared and connected will be key to unlocking opportunities and maintaining a competitive edge.
