European Equity Market Structure Review

Record volumes again. European equities have set a seventh consecutive seasonal record.

The summer trading period delivered the seventh consecutive record-breaking quarter for trading volumes, measured against their seasonal counterparts. Q3 beat the 8-year average for both Q1 and Q2 since MiFID2 began, using inflation-adjusted data.

The usual summer slowdown arrived in proportion to previous years, but from a far higher base. Every month in Q3 set a record for its corresponding calendar month. The September index expiry produced the third-largest trading day in 8 years and probably ever. Here are the main highlights.

• Highest Q3 average daily trading value (ADVT) on record: €71.4 billion per day, 13.3% above the previous best Q3 in 2025 and 29% above the Q3 average since 2021.
• Every month of the quarter set a record for its calendar month: €75.2 billion in July, €65.6 billion in August and €73.0 billion in September.
• The September index expiries generated €164.4 billion, the third-largest day on record, including a €63.6 billion Closing Auction, second only to the index review in May.
• Vodafone shares marked the third-largest single-stock day since 2018 in real terms, generating €11.1 billion, off the back of an ECM transaction between two shareholders.
• Equity ETFs traded a record Q3 average of €13.0 billion per day, the third highest quarter yet, 40% up on Q3 2025 and 3x the 13% growth of the equity market.
• ASML reached a record 3.4% share of European value traded, averaging €2.4 billion per day, reflecting the ongoing appetite for AI supply chain shares.
• The Closing Auction set a new high of 28.4% of order book trading, while Periodic Auctions gave back share for a third consecutive quarter, to 10.1%.

Fully 86.4% of Q3 trading days were above the long-run median of €59.8 billion, against 57.6% in Q3 2025. The seasonal drop from Q2 to Q3 was 17.7%, slightly less than the average summer drop of 20%, reinforcing the trend towards a new level for European equities investment and greater market resilience to the macro picture.

Market volumes are essential inputs for all aspects of the investment cycle. Managers can observe patterns in investments flows, use liquidity indicators to evaluate exit and entry costs during asset selection, and their traders use the data to guide their execution algorithms. As the markets churn out billions of data points a day, precision and accuracy is everything. Read the Review for a high level summary built from the data and insights we provide every day.

A Record Q3, With the Usual Summer Dip, but from a Higher Level

Trading volumes in Q3 2026 averaged €71.4 billion per day in real terms, 13.3% above the previous best Q3 in 2025 and 29% above the Q3 average since 2021. Q3 normally marks the lowest quarterly volumes of the year, and this one was no exception, but every month of the quarter set a new record for its calendar month.

We have noted in the past that record volumes are closely related to price volatility and are often followed by long periods of drought. But in Q3 volumes have remained elevated despite falling volatility, suggesting equity market resilience and potentially higher investment inflows. This is reinforced by equity ETF volumes reaching a Q3 record, growing three times faster than the equity market (we look at how much of this is focussed on European underlyings later). This presents a conundrum; higher bond yields, increasing energy costs, ongoing conflicts and increased political focus on AI would normally indicate investors moving out of equities.

The drop from Q2 to Q3 was 18%, slightly smaller than the average summer drop of 20% since 2018. The table shows that the first half of the year has been more active than the second in every year since 2020, as geopolitical shocks, annual reporting and large index events cluster in H1. With Q3 in hand, H2 2026 is on course for a drop from H1 that is in line with the 15% of 2025 rather than the 30% of 2020 and 2022 (the risk-off years). 

¹See Methodology section at the end of the review for explanation of Addressable Liquidity

Index Events Still Set the Peaks

The daily view shows the distribution of European trading activity across more than 1,700 sessions from January 2020 to September 2026. The data shows that the mean reverting level (which is inflation adjusted) is not stationary and has been trending upwards for two years, signalling a new regime. The September index expiry on 18 September traded €164.4 billion, the third-largest day on record behind the semi-annual review on 29 May (€194.9 billion) and the March expiry (€175.3 billion). Four days in the last 12 months have exceeded the €143 billion recorded at the height of the Covid crisis.

The median inflation-adjusted ADVT for the full period is €59.8 billion. In Q3 2026, 86.4% of trading days were above that median, compared with 57.6% in Q3 2025, and the lowest day of the quarter still traded €44.6 billion. The cluster of days above the median has now extended through a full summer, without the pink-band volatility that drove the H1 peaks.

Equity ETFs Floating on the Rising Tide, but pure European underlyings lag other regions

Equity ETFs traded a Q3 record of €13.0 billion per day, 40% above Q3 2025 and three times the 13% growth rate of the European equity market. Equities accounted for 74.9% of European-listed ETP trading, up from 68.2% a year earlier and above their 8-year average of 66.1%.

ETF data adds a different dimension to the cash market, because European listings cover underlying equities from around the world. Looking at trading volumes by the region of the underlying gives a sense of where European investors seek equity exposure, geographically.

Volumes in ETFs with purely European underlyings are growing, but more slowly than globally diversified products or those focused on other regions. ETFs with pure developed European exposure set a record Q3 of €2.45 billion per day, up 6% year on year, against increases of 33% for pure North American exposure, 60% for global and developed market products and 86% for emerging markets. Pure European focus ETF's share of all equity ETF trading has fallen over the long term from 45.7% in 2018 to 19.1% in Q3, close to the low of 18.5% in Q4 2024. The data suggests an appetite for more global diversification or a general trend to tilt towards other regions.

Doing the same for ETF listings in other regions, which are available to non-European investors, together with primary market data, creates a comprehensive picture. As this is beyond the scope of this review it will be covered in a forthcoming Liquidity Matters series, so please look out for this on our website.

The Tape Goes Live: From Reported to Addressable Liquidity

On 14 September, the European Consolidated Tape for equities and ETFs went live, one of the biggest structural changes to European equities in two decades. For the first time, quotes and trades from across EU and EEA venues flow through a single standardised feed, creating a European Best Bid and Offer (EBBO) from a common, regulated source in an effort to counter nearly 20 years of European price fragmentation: so far in 2026, some 560 leading EU and EEA stocks have traded across nearly 30,000 distinct pools of liquidity.

The tape works on two levels. The pre-trade tape builds an EBBO from lit venues, which account for 40% of total reported value traded, or €33 billion a day year to date. The post-trade tape reports trades from all sources: €82 billion a day. Not all of that is 'addressable', that is, it forms a pool of liquidity that is both price forming and that can reasonably be accessed by the majority of market participants. Technical and non-price-forming trades, such as give-ups and inter-group transfers, account for around €25 billion a day. Once they are removed, addressable value is around €57 billion a day, and the lit venues feeding the EBBO represent 58% of it, a much stronger basis for measuring execution quality. The more accurate 'addressable' figure is crucial to optimising trading costs, given that most institutional trades are executed using some level of participation rate which must be based on realistically accessible market flows.

Unlike the US NBBO, the EBBO is not mandated as an execution benchmark, and firms keep their own best execution policies under MiFID II. Even so, it is very likely to become a reference price, and brokers and fund managers should be ready to explain how their execution compares. The full analysis is in Liquidity Matters Episode 17.

Health Care Steadies, Defence Cools

Given the macro environment, it might be expected that the sector data would see a stronger concentration towards Energy, the AI supply chain and European defence. Yet Energy stayed in 8th position, gaining only 11bps market share and Information Technology (containing semiconductors) maintained the third place gained in Q2, but slightly lost market share. Industrials (including Defence) lost 1.41%. There was less rotation than from Q1 to Q2, with only two of the top sectors changing position, and only two changing their market share by more than 50bps.

Health Care was the most resilient sector. Its trading volume fell only 6.7% from Q2, against an 18% drop for the market, lifting its share by 1.3% to 10.1% and into fourth place. The move was concentrated in large names: AstraZeneca rose to third in the stock rankings and Roche to eighth, recovering partly from a quieter Q2.

Industrials saw the steepest decline in volume of any sector, down 23% from Q2, with defence names leading the retreat. Rheinmetall, second in the rankings in Q4 2025, fell to 17th. Taken together, the shifts look more like stock-specific stories inside sectors than a broad rotation between them.

ASML Extends Its Lead as the Rankings Reshuffle

Single-stock rankings indicate the level of concentration in the top European shares. The average market share of the top 10 names in any quarter since 2018 hovers around 14.4%; the data is not seasonal and mean reverts suggesting this concentration is quite stable.

ASML continues to rank first in Q3, beating all previous quarters but two (Q1 and Q2 2026), with €2.42 billion ADVT and a record 3.39% share of market flows. The chart shows the change in market share of trading volumes for any stocks that spent at least one of the last four quarters in the top 10, ranked by ADVT€. The list has contained between 13 and 16 names since 2024, although as the chart shows, there is substantial movement in and out of the category.

SAP returned to second. AstraZeneca was the largest climber, from 21st in Q2 to third, with ADVT up 43%. The semiconductor names that surged in Q2 eased back, with Infineon ending sixth from third and STMicroelectronics from seventh to 12th, while Siemens Energy dropped from second to fifth.

Rheinmetall's slide continued, to 17th from second in Q4 2025, and Novo Nordisk sits at 29th, a long way from fourth a year ago. Roche's history is stitched across its March 2026 ISIN change; on a continuous basis it ranked eighth in Q3.

Outside the chart, Vodafone printed €11.1 billion on 15 July, the third-largest single-stock day since 2018 in real terms, behind Carrefour in September 2021 and Unilever in November 2020. The purchase of e&'s stake by a consortium of banks, and concurrent sale (via structured products) to an existing shareholder of up to nearly 20% of Vodafone was an ECM event. Both legs represent real market liquidity and will result in the banks unwinding derivative positions to deliver shares over the next 12 months. The trade takes Vodafone ADVT from €165 million a day to €330 million a day for the quarter, which is not a useful number for ADV calculations and inputs to smart routers and algorithms because of this enormous event. This is an instructive example of the need for careful curation of off-order-book trade reports into addressable liquidity, which we will cover in a future episode of our blog, Liquidity Matters.

Dark Pools turn the tables on Periodics, Closing Auction Sets New Record

It’s a year since the 8% cap on trading in dark venues was reduced to 7%. Since then, Periodic Auctions and Dark Pools have been in a tug of war. Periodic Auctions gave back share for a third consecutive quarter, to 10.1% from a peak of 12.2% in Q4 2025. Over the last three years Lit Continuous has surrendered 8.6% of share, and Periodic Auctions still account for 5.1% of it, but the momentum of 2025 has stalled.

The Closing Auction reached a new high of 28.4% of order book trading in Q3, taking market share in five of the last six quarters and setting a second consecutive record. While the long-term trend toward end-of-day trading has slowed, the Close could yet reach the 30% of electronic trading. Lit Continuous edged up to 47.7%, but hardly a rebound from its post MiFID/MiFIR low of 47.3% in the last quarter.

The lower panel shows the quarter-on-quarter changes. Lit Continuous typically regains share only at the onset of high-volatility periods, when real-time risk management takes priority. With volatility lower for most of Q3 2026 and with Periodic Auctions slightly lower, perhaps the elevated level of general liquidity is arresting further reductions in lit order book market share.

Conclusion

Volume Data as the Market's Weather Radar

Why use volume data to investigate market trends? Monitoring volume distribution over time, among sectors, single names and in the ETPs gives an instant read-out on flow momentum, investor risk appetite and market sentiment, crucial for both asset allocation and security selection. Information from monthly surveys, AUM reports and market consensus is lagged. Volume data is updated intraday and integrated with both short- and long-term patterns, helping a portfolio manager form a view of where the market is heading next. It is also a source for detecting activity when information has not been widely broadcast.

Simplistically, sudden spikes in trading activity that are out of line with recent trends indicate new momentum, especially when those volumes are sustained. Bullish trends tend to drive less volatility in volumes and are more sustained, as we have seen with the Semiconductors sector.

Health Care in Q3 is a good example. While the market adhered to the seasonal trend, trading 18% less than in Q2, Health Care volumes reduced by just 7%, driven by AstraZeneca and a recovery in Roche volumes. A sector that looked like a source of outflows in the first half, as Novo Nordisk slid down the rankings, held its ground over the summer, and volume data showed it before any quarterly fund flow report.

If you want to know more about our regular observations about market structure and volume patterns, join our growing community of followers on our ‘Liquidity Matters’ blog site at xyt.one/insights.

Methodology

Universe Definition

This review covers trading activity in the constituents of the large and mid cap country level equity indexes for 16 European Countries and is used as the reference universe consistently throughout the report, unless shown. Aggregating at index level, rather than by individual exchange, captures fragmented liquidity for each underlying stock across all trading venues, avoids double counting from cross-listings, and keeps the comparison like-for-like as constituent membership evolves from quarter to quarter. Where a stock changes ISIN, its history is stitched into one continuous series.

Inclusion of OTC Trading

The review refers to 'addressable' liquidity throughout unless stated. This means we count flows that can realistically be accessed by most market participants to execute their trades. The value traded figures combine all on-order-book execution venues (Lit Continuous, Periodic Auction, Dark and Closing Auction) with over-the-counter (OTC) reported trades, consistent with the exchange-reported data series used in the Seasonal, Daily and Market Share sections. Technical and non price forming trades are removed. Sector and stock-level splits are calculated on the same combined on- and off-order-book basis unless a chart states otherwise. Historical figures are restated each quarter to accommodate alterations to the trade reporting conditions.

Inflation Adjustment

All monetary values in this review are expressed in real terms, adjusted for European price inflation using an ADVT-specific GDP Inflator series. The anchor month for this edition is September 2026, set to an inflator value of 1.0; earlier months carry an inflator above 1.0, reflecting lower nominal prices in those periods.