Market status · 5 min read
What is a trading halt—and why has the stock stopped moving?
Learn what a stock trading halt means, how to check official halt codes and resumption times, and how to distinguish a halt from inactive or delayed data.
When a chart stops updating, establish the market status first. No recent trades, a data connection problem, and an official halt can look similar while meaning different things. A frozen display does not identify the cause.
Check the observation window first
Verify ticker, trading date, session, and feed timestamp. Check whether other securities still update. A single frozen window can reflect filtering, permissions, or connectivity. Last may remain unchanged even while quotes move if no eligible execution occurs.
These checks do not rule out a halt. Cross-check the security and time against Nasdaq Trader’s current halt list, which labels times in Eastern Time. Use the session guide to align time zones.
Different codes mean different reasons
Nasdaq Trader’s official code table distinguishes causes and resumption states. Examples include:
| Example code | Meaning |
|---|---|
| T1 | Material news pending |
| T12 | Additional information requested |
| LUDP | Volatility trading pause |
| H10 | SEC trading suspension |
A volatility pause is not a news-pending halt. An individual-stock pause is not a market-wide circuit breaker. Do not reduce every mechanism to a five-minute wait. FINRA explains halts, delays, and suspensions.
When does an LU or LD indication become a volatility pause?
LU and LD usually refer to the upper and lower LULD bands, or platform labels for related states. A price band, a Limit State, and a declared Trading Pause are distinct. Touching a band does not confirm a pause. During regular hours, an unresolved 15-second Limit State leads to the specified pause process; other state-specific provisions also apply.
For moving-band calculations and why reopening after five minutes is not guaranteed, read the LU, LD, and LULD guide. It explains the volatility mechanism; this article covers the broader halt and order-status checks.
Quotes and trades may resume at different times
An official record can show separate quote and trade resumption times. The first does not establish that executions have resumed. Scheduled times can also change; read the latest status instead of relying on the original countdown.
In a fictional record with quotes scheduled for 10:15 and trading for 10:20, seeing a quote at 10:16 is insufficient evidence of resumed trading. See Nasdaq’s field definitions.
Check orders independently
A pause does not mean all outstanding orders have been canceled. Acceptance of new orders, changes, and cancellation requests depends on broker and venue rules. Clicking cancel is distinct from receiving a cancellation confirmation.
The resumed price can differ from the pre-halt price. The distinctions in stop and stop-limit mechanics still matter: a trigger does not guarantee price, and a limit does not guarantee execution.
Retain market-status evidence in a review
After finding a historical sample in the Top Gappers Calendar, investigate a chart gap using official records and company sources. A blank chart interval does not establish a halt, and HOD Timeline is not a substitute for status records.
Keep this evidence with notes in the FennEdge workspace. The glossary can help decode unfamiliar abbreviations.
This article explains common concepts; examples are not trading recommendations.
