May 21, 2026/IOSCO

The International Organization of Securities Commissions (IOSCO) published today its Consultation Report regarding Regulatory Considerations and Good Practices on the Evolution of Market Liquidity during the Trading Day and its Report on Extended Trading Hours.

IOSCO is seeking feedback on its Consultation Report on the Evolution of Market Liquidity during the Trading Day. Equity market structures continue to evolve, with technological developments and trading strategies contributing, in many jurisdictions, to a growing concentration of trading activities at the close. While deeper closing auctions may support price discovery and efficiency, they may also introduce risks, including reduced liquidity during continuous trading, increased susceptibility to market manipulation, heightened volatility around the close, and operational and resilience challenges for trading venues.

The consultation report presents the findings of a global stocktake conducted by IOSCO, drawing primarily on input from regulators and engagement with trading venues. It analyses how liquidity is distributed throughout the trading day, the implications of evolving liquidity patterns and auction designs, and the effectiveness of existing regulatory and supervisory approaches. Based on this analysis, IOSCO proposes a set of good practices intended to assist regulators and trading venues in preserving fair, orderly and resilient equity markets as trading patterns evolve.

Separately, interest in extending trading hours beyond traditional sessions, including overnight or near-continuous trading, has been growing in some jurisdictions. The Report on Extended Trading Hours reviews proposals and practices relating to equity markets across IOSCO jurisdictions and examines their potential benefits and risks. It finds that trading outside core trading hours varies across jurisdictions and remains predominantly retail-driven, with limited institutional participation. Where introduced, extended trading hours is typically venue-led, upon the demand of market participants, and is characterised by lower liquidity, wider bid–ask spreads and adjusted execution conditions compared with regular trading hours.

The report also highlights that regulators have largely focused on assessing whether existing regulatory frameworks for market integrity, disclosure, surveillance, and operational resilience, are sufficient to address extended trading hours, rather than introducing bespoke regulatory regimes. Trading venues have considered risk controls and operational arrangements to mitigate lower liquidity and execution risk, while operational capacity, staffing, post-trade processing and the transition to shorter settlement cycles have emerged as key practical considerations.

This report focuses on equity trading, and IOSCO does not exclude further work on related areas impacted by the emerging practice, such as asset management, valuations, risk management or derivatives, etc.

Comments on the Consultation Report regarding Regulatory Considerations and Good Practices on the Evolution of Market Liquidity during the Trading Day may be submitted using this form on or before 21 August 2026.

If you require technical assistance on completing the survey, please contact itsupport@iosco.org.

If you have questions about the content of the report or the consultation, please contact ML2026-consultation@iosco.org.

“International markets are evolving in ways that call for careful, up-to-date assessment and international dialogue. Through these publications, IOSCO is supporting a shared understanding of developments that may affect how markets function over the course of the trading day. The consultation on intraday liquidity is a good opportunity for stakeholders to inform IOSCO’s consideration of whether existing regulatory and supervisory approaches remain fit for purpose as market practices continue to change.”

Jean-Paul Servais, IOSCO Board Chair

“Interest in extended trading hours is rising in some markets, and the report provides a factual assessment of current practices, observed market conditions and key regulatory issues, relating to equity markets. In parallel, the consultation on the evolution of market liquidity during the trading day responds to the increasing concentration of trading at the close and seeks feedback on proposed good practices aimed at supporting fair, orderly and resilient markets.“

Martina Tambucci, Chair of IOSCO’s Committee on Regulation of Secondary Markets, Head of International Relations Unit, Commissione Nazionale per le Società e la Borsa, Italy