Overnight trading in U.S. equities is entering a new phase, with rising volumes, deeper liquidity, and broader participation accelerating the shift toward a more continuous trading model, according to executives from Exegy, Blue Ocean ATS, Bruce ATS, and BMLL who joined a recent webinar examining the infrastructure changes reshaping U.S. markets.
During the discussion, 24/5 Trading: The Infrastructure Shift Behind Always-On Markets, industry leaders explored how overnight trading has developed from a niche offering into an increasingly important part of the equity market ecosystem.
For Blue Ocean ATS, the growth has been significant. When the venue launched in 2021, overnight trading was still largely untested, according to John Willock, Head of Strategy, Blue Ocean Technologies.
“Blue Ocean started in 2021. At that point, there was nothing. It was very much an experiment in so many ways to see if something would happen. At the point I joined the company, which was early 2023, we were doing maybe a million shares a night, and that was a decent quality night. On a notional basis, perhaps tens of millions of dollars,” he said.
“Over the course of early 2026, we’ve exceeded $10 billion on a notional basis in a single session, and into the hundreds of millions on an average basis in certain months in recent past, well over $100 million on average,” Willock said.
The market now covers thousands of securities, according to Willock.
“It’s grown massively, and that’s across maybe eight or 9,000 different unique instruments over the course of a month,” he said.
Despite the growth, overnight trading remains a small percentage of overall U.S. equity activity.
“In the grand scheme of things, even these relatively large numbers are still perhaps 1% market share of the total U.S. equities trading volume pie,” Willock said.
“In some ways big, in some ways bigger than some national exchanges, funnily enough, but still actually quite small in the U.S. overall scale.”
The customer profile has also evolved from retail-focused activity toward greater institutional participation, he said.
“Going from heavily retail to start with, a few market makers to be their counterparties, to then increasingly up the institutional chain of user types,” Willock said.
Competition drives market maturity
Jason Wallach, CEO of Bruce Markets, said competition among overnight venues has accelerated market development.
“The average volume per session from June in 2025 to 2026 has gone from 25 million shares a night to 250 million shares executed a night across three ATSs,” Wallach said.
“From a notional perspective, it’s one and a half billion per night to $8.6 billion in June,” he said.
Wallach said the evolution is about more than trading volume: “It is both broader adoption, but it is also what we’ve seen is really this maturation of the market.”
The arrival of multiple venues has introduced new capabilities, including smart order routing and additional order types, he said.
“We now have three ATSs operating overnight. That competition brings a number of things. It’s brought innovation. We’ve seen new order types hit the market. We’ve seen the introduction of smart order routing,” Wallach said.
According to Wallah, liquidity has also improved: “We’ve seen spread compression and increased liquidity to the levels of 9,000 unique symbols being quoted a night on Bruce ATS. The liquidity has grown. The market has grown. It’s become more robust.”
Data points to stronger liquidity
For Elliot Banks, Chief Product Officer at BMLL, the key shift has been the improving quality of overnight liquidity.
“A big part of it isn’t just volume, but the overall liquidity picture,” Banks said.
He said market data shows overnight activity increasingly resembles traditional trading sessions: “You’re seeing volume smiles in the same way you would see that during a day session, indicating sort of a real flow type behavior that’s there.”
He also said that the composition of trading has broadened: “It’s not just certain stocks. It’s not just certain ETFs. If you were to look at the makeup of names that were trading during an overnight session, it looks very much like what you see on a day session,” Banks said.
The panel said market attitudes have shifted from simply exploring overnight trading to incorporating it into trading strategies.
“In the beginning there was a lot of interest in just understanding. What is this? Is this something that I want to use?” Banks said, adding that has changed as firms have gained access to better data and analytics.
“Now we’re getting people saying, actually, I’m trading this, or I’m looking to build strategies on this. The narrative has shifted from ‘this is something I should probably understand’ to ‘this is something I need because it’s built into my trading workflow,’” he said.
Regulation and the road ahead
As overnight trading becomes more established, regulation is moving toward greater integration with existing market infrastructure.
“The regulators have laid out the exact plan. The exchanges have issued their filings and have received approval for those where necessary. The consolidated tapes have received their appropriate approvals for 23 by 5,” Willock said.
He added that future changes will include additional transparency requirements.
“That will include calculation of a national best bid and offer. That will include real-time TRF reporting,” he said.
Wallach said maintaining execution quality will remain critical.
“The overwhelming top priority item here is to make sure that we do have a strong sense of market integrity and opportunities for investors to know that if they choose to participate in the overnight trading session, that their orders are being executed at the best price possible under prevailing market conditions,” he said.
The panel also discussed whether equities could eventually move toward 24/7 trading.
“There’s absolutely no reason I see that our markets need to be closed or should be closed. The demand to react to that news will only grow,” Wallach said.
For Willock, the ultimate measure of success is when overnight trading becomes routine: “Success for me would mean that it’s table stakes.”
“There is essentially no need to ask your broker whether they have that overnight capability. It just is there as it would be during the middle of any normal weekday,” he said.
