23-hour US stock trading expected to start 6 December, subject to SEC approvals

Twenty-three-hour trading on US stock exchanges is expected to start on Sunday 6 December. The date is a plan, not a certainty: each exchange still has regulatory steps to complete before its overnight session can go live.

Exchange by exchange

NYSE Arca. “Subject to SEC approvals, the availability of the Securities Information Processors (SIPs), and the implementation of the Depository Trust and Clearing Corporation’s (DTCC) modernization efforts, NYSE Arca plans to launch extended-hours trading on December 6, 2026,” the exchange says in its extended-hours FAQ. It would trade from 9:00pm to 8:00pm ET, five days a week, with a new Overnight Session from 9:00pm to 4:00am. In a May rule filing, NYSE Arca said it “will file another rule change with the Commission before activating 23/5 Trading”, once the equity data plans confirm they are ready.

Nasdaq. The SEC approved Nasdaq’s proposal to trade 23 hours a day, five days a week on 10 April, with a Day Session from 4:00am to 8:00pm ET and a new Night Session. Nasdaq has told members in a trader alert that “on December 6, 2026, Nasdaq will introduce a new trading session from 9 p.m. to 4 a.m. ET”. The approval order notes that Nasdaq will not start the Night Session before filing a further proposed rule change confirming that it, and the equity data plans, are ready.

Market data, trade reporting and clearing

The SEC approved amendments to the CTA/CQ and UTP plans on 26 June, allowing the SIPs to extend their hours. Both SIPs give an implementation date of 6 December, “dependent on Listing Exchange readiness and regulatory approvals”, according to the CTA and UTP FAQs. The SIPs would run from 9:00pm ET on Sunday to 8:00pm ET on Friday, with a daily pause of under an hour. CTA plans a pre-launch period from 8 November to 5 December, with test symbols only.

FINRA says its trade reporting facilities will extend their hours to support 23x5 reporting from 6 December, with a one-hour pause each weeknight at 8:00pm ET. NSCC has already moved: DTCC said on 29 June that clearing now runs from 8:00pm ET on Sundays to 8:00pm ET on Fridays. In a 12 October technical notice, FINRA reminded firms that use correspondent or QSR clearing relationships that they must set up separate 9A/9B relationships for the overnight session; otherwise trades accepted at a TRF could be rejected at NSCC.

What we are watching

• The further rule filings NYSE Arca and Nasdaq must make before activating overnight trading, and whether the 6 December date holds.
• Results of the SIPs’ industry testing and the CTA pre-launch period.
• How much volume moves to exchange overnight sessions once they are live.

Updated 26 October 2026: this article has been revised to rely solely on exchange and regulatory sources. The 6 December date is NYSE Arca’s planned launch and the SIPs’ implementation date, and remains subject to SEC approvals and further exchange rule filings. A figure for the current overnight share of US stock volume, which came from news reports, has been removed.