dxFeed has published a venue-by-venue testing calendar for expanded US equities trading hours, with the planned production launch beginning Sunday 6 December for the 7 December trading day. The service maps an overnight session beginning at 21:00 Eastern Time to next-day trading records. That is a data-processing change as well as a longer market session; a broker that assigns late Sunday or Monday evening trades to the wrong date can corrupt intraday metrics and customer statements.[1]
The reported regular session remains 09:30–16:00 ET, followed by the 16:00–20:00 late session. An overnight segment runs 21:00–04:00 and connects to 04:00–09:30 premarket. dxFeed treats that full 21:00–09:30 period as one logical premarket session under the next trading day ID.[1]
Tests do not open simultaneously
Published staged test calendar
| Venue or service | First specified test | Scope |
|---|---|---|
| Nasdaq | 1 Nov | ZXZZT, ZVZZT, ZWZZT overnight symbolsSource 1 |
| CTA / NYSE Arca | 8 Nov | Start-of-day changes / Arca test symbolsSource 1 |
| Cboe EDGX | 9 Nov trade date | ZBZX and ZTST; Cboe One feedSource 1 |
| MEMX | No advance production test | No prelaunch symbols promisedSource 1 |
| Full session plan | 6 Dec for 7 Dec trade date | Nightly pause, weekend closure remainSource 1 |
Nasdaq test-symbol trading is scheduled from 1 November, using ZXZZT, ZVZZT and ZWZZT. CTA and NYSE Arca testing begins from 8 November, including NTEST, PTEST and ATEST on Arca. Cboe EDGX test symbols ZBZX and ZTST become available for the 9 November trading date. MEMX does not plan advance production test symbols, while 24X is among the venues participating in expanded hours.[1]
dxFeed plans to disseminate the test symbols through its demo endpoint so clients can check subscriptions, venue attribution and ingestion. Broker order-entry readiness is a separate test: a successful data subscription does not establish that the broker accepts overnight orders in that security.[1][2]
Overnight is not weekend trading
From Sunday 21:00 through Friday 20:00 ET, the schedule includes maintenance pauses Monday to Thursday from 20:00 to 21:00. The Friday-to-Sunday gap is a full weekend closure, not the same one-hour pause. Real-time SIP dissemination is unavailable during both.[1]
The key readiness question for technology teams is whether orders, quotes, timestamps, corporate-action adjustments and end-of-day reporting agree on the same logical trading date. A user interface that shows a continuously streaming quote may still conceal an attribution or routing defect; the staged test calendar exists to find such errors before the proposed December production switch.[1]
Sources & further reading
- 23x5 testing opportunities and go-live readiness dxFeed · 27 Oct 2026 · Accessed 30 Oct 2026
- Market data service announcements dxFeed · Accessed 30 Oct 2026