24X National Exchange has scheduled six overnight industry tests ahead of a target 6 December 2026 launch of 23-hour weekday equity trading. The published calendar places the second rehearsal on 16 October and the next on 30 October. Members and infrastructure providers use the windows to validate connectivity, session handling, order logic, market data and the evening reset.[1]
The wider market plumbing is further advanced than the exchange calendar alone suggests. NSCC extended clearing to a 24x5 model on 29 June, operating from Sunday 8pm to Friday 8pm Eastern Time and applying its central-counterparty guarantee to eligible overnight transactions. DTCC identifies December 2026 as the milestone for the first exchanges and Securities Information Processors to move to 23x5 operation.[2][3]
Launch and infrastructure at a glance
| Measure | Value | Context |
|---|---|---|
| Second scheduled industry test | 16 October 2026 | Second of six scheduled tests; tests begin Friday at 11pm and finish Saturday at noon.Source 1 |
| Target production launch | 6 December 2026 | The date remains a target and depends on readiness across the exchange, SIPs, members and related approvals.Source 1Source 4 |
| NSCC clearing window | Sunday 8pm–Friday 8pm ET | The post-trade clearing extension is already live.Source 2Source 3 |
| Daily exchange pause | 8pm–9pm ET | Orders are not accepted during the pause and sequence numbers reset then, not at midnight.Source 1 |
Six tests, one production target
Pre-launch timetable
| Date | Status | Purpose |
|---|---|---|
| 2 October | Scheduled test date (past) | Initial overnight industry rehearsalSource 1 |
| 16 October | Scheduled test date (past) | Second connectivity and session testSource 1 |
| 30 October | Scheduled | Further member and infrastructure testingSource 1 |
| 6 November | Scheduled | Operational rehearsalSource 1 |
| 20 November | Scheduled | Late-stage readiness testSource 1 |
| 4 December | Scheduled | Final test before the target launchSource 1 |
| 6 December | Target launch | Production overnight sessionSource 1Source 4 |
The planned model is near-continuous rather than continuous. Trading crosses midnight without a session break, but the 8pm-to-9pm pause preserves a single US trade-date boundary. That boundary matters to clearing, reporting and operational reconciliations. A trade executed after the reset belongs to the next trade date even if the local calendar date elsewhere has not changed.[1][3]
Members need matching session, data and clearing configurations
The SEC approved longer operating hours for the consolidated Securities Information Processors, with the new schedule set for 6 December. 24X expects existing production connectivity to support the overnight session without a separate dedicated port. Its FAQ also specifies support for NSCC’s TradingSessionID and ClearingBusinessDate fields, and direct MEMOIR top-of-book, depth-of-book and last-sale feeds during extended hours. These details make the session and trade-date mapping a concrete part of member testing.[4][1]
How the overnight session differs
| Feature | Published treatment | Practical consequence |
|---|---|---|
| Trade reporting | Overnight and after-market trades carry the T condition and enter consolidated volume | An overnight print is reported, but it is not treated as a regular-session last saleSource 1 |
| Reference prices | Price controls will be enabled | A venue can reject or constrain orders beyond its controls; the final detail still needs exchange communicationSource 1 |
| Corporate actions | Special halt and processing standards apply | A split, dividend or other action can require treatment different from an ordinary uninterrupted sessionSource 1Source 4 |
| Liquidity | No guaranteed minimum depth | Access at 3am does not imply regular-session spreads or executable sizeSource 1Source 4 |
Direct access is limited to US broker-dealers that are 24X members; some also require clearing-firm approval. Retail participation therefore depends on the customer’s broker connection, enabled instruments and order controls. The exchange’s target remains dependent on SEC approval and infrastructure readiness.[1]
The remaining published rehearsals culminate on 4 December. Bringing the exchange, consolidated data and extended clearing into the same overnight model requires each participant to handle the evening reset consistently while maintaining the distinct execution and corporate-action controls shown above.[1][3]
Sources & further reading
- Overnight Trading FAQs and industry test schedule 24X National Exchange · Accessed 16 Oct 2026
- NSCC now live with 24x5 clearing hours DTCC · 29 Jun 2026 · Accessed 16 Oct 2026
- 24x5 trading for US equity markets: milestones and operating window DTCC · Accessed 16 Oct 2026
- Stock Around the Clock: remarks on preparations for 24-hour trading US Securities and Exchange Commission · 17 Sep 2026 · Accessed 16 Oct 2026