Equity market data for quarter ending September 2025

ASIC receives equity market data through our market surveillance system. This system captures all orders and trades in Australian equity market products and is the primary source of equity market statistics reported by ASIC. This page presents summary statistics, tables and charts on market characteristics, including measures of market efficiency, volatility and concentration.

For an explanation of the measures used in this release, see Information Sheet 177 Quarterly cash equity market data: Methodology and definitions (INFO 177).

Summary for quarter ending September 2025

In the September 2025 quarter, ASX accounted for 82.1% of the total dollar turnover in equity market products. Cboe accounted for the remaining 17.9% of total dollar turnover. This is an increase in ASX’s market share from last quarter where it was 81.3%. These figures include all trades executed on order book, as well as trades matched off order book and reported to either market operator. On order book turnover (excluding ASX auctions) as a proportion of total dollar turnover increased to 56.8% in the September quarter from 55.7% in the June quarter. Trade reporting turnover as a proportion of total dollar turnover increased to 19.3%, compared to 19.0% in the June quarter.

ASX’s market share, measured by the Herfindahl-Hirschman Index (HHI) measure of market concentration of public order book volumes, remained at 0.65 in the September quarter (maximum 1.00).

Daily Turnover in the Australian equity market decreased by $0.1 billion from the June quarter to an average of $9.7 billion for the September quarter.

The overall order-to-trade ratio decreased from 9.3:1 in the June quarter to 8.1:1 in the September quarter.

Depth of the orderbook across the best bid and ask in the September 2025 quarter reached an average of $723,000 across the largest 200 securities and $701,000 across all securities, compared to $764,000 and $716,000 last quarter, respectively. Quoted spreads in the September quarter have decreased for the largest 200 securities, currently at an average of 11.46 bps from 11.60 bps last quarter. Across all securities, quoted spreads have increased, at 21.61 bps from 19.70 bps last quarter. Effective spreads have increased across the largest 200 securities, at 10.39 bps from 10.34 bps last quarter, and increased across all equity products, at 19.48 bps in the September quarter from 17.67 bps previously.

Table 1: Market characteristics – average for September quarter 2025

Statistics	ASX on book	ASX Auctions	ASX Centre Point	ASX trade reporting	Cboe on book	Cboe trade reporting	Total	Change from previous quarter
Number of trades per day	1,731,505	75,645	372,016	60,348	661,126	99,471	3,000,113	▲
(market share)	57.7%	2.5%	12.4%	2.0%	22.0%	3.3%	100.0%
Value traded ($ million/day)	3,851.7	2,304.2	667.9	1,111.2	977.2	758.4	9,670.6	▼
(market share)	39.8%	23.8%	6.9%	11.5%	10.1%	7.8%	100.0%
Order-to-trade ratio	7.0	na	6.1	na	12.1	na	8.1	▼
Average trade size ($/trade)	2,229.5	30,296.6	1,797.7	18,325.1	1,479.6	7,594.8	3,220.4	▼

Table 2: Measures of market concentration

Statistics	Sep 2024	Jul 2025	Aug 2025	Sep 2025	Change from previous quarter
Total market	0.42	0.44	0.41	0.43	▼
Public venues	0.65	0.65	0.64	0.65	-

Table 3: Measures of market efficiency

Market Efficiency Statistics	Sep 2024	Jul 2025	Aug 2025	Sep 2025	Change from previous quarter
Quoted bid-ask spread (bps)
Top 200 securities by turnover	12.07	11.65	10.76	11.97	▼
All Securities	19.23	21.63	20.25	22.96	▲
Effective bid-ask spread (bps)
Top 200 securities by turnover	10.44	10.48	9.80	10.88	▲
All Securities	16.85	19.38	18.24	20.82	▲
Best depth ($)
Top 200 securities by turnover	561,702.53	813,898.59	660,058.53	693,638.33	▼
All Securities	549,970.71	766,114.15	664,303.66	672,479.34	▼