Real-Time and Delayed Market Data
Market data is licensed, and a delayed feed is a licensing outcome rather than a technical one. Knowing which you are looking at matters for anything time-sensitive.
MadStockAlerts Research · Updated August 28, 2026
What to take away
- Exchanges own their price data and license it, which is why delayed data exists.
- A 15-minute delay is the long-standing convention for free distribution.
- Delayed data is accurate; it is simply behind.
- For longer-horizon analysis the delay is usually immaterial.
- The delay affects the right-hand edge of a chart and nothing else.
MAD Academy Training Video · 0:45
Fifteen Minutes Is a Long Time
Delayed data is accurate and old, which is fine for analysis and quietly dangerous for execution.
This lesson is part of a Stock Alerts + Tools plan.
Why a delay exists at all
Exchanges treat their quote and trade data as a product. Real-time distribution is licensed and paid for, per user and per venue, while delayed data is licensed on far cheaper terms.
The delay is a commercial boundary, not a limitation of any system. Nothing technical prevents a free site from showing a current price; the licence does.
What actually differs
| Real-time | Delayed | |
|---|---|---|
| Accuracy of the values | Identical | Identical |
| Age of the last point | Effectively current | Typically 15 minutes behind |
| Historical bars | The same once settled | The same once settled |
| Suitability for timing | Yes | No |
| Suitability for research and levels | Yes | Yes |
The delay affects the right-hand edge and nothing else. A 200-day moving average computed on delayed data is the same line. A decision about whether price is through a level right now is not something delayed data can answer.
- 1The trade prints on an exchange
- 2Consolidated onto the tapeMilliseconds
- 3The entitlement checkReal time, or held for fifteen minutes
- 4Your screen
Where the delay does matter
- Around an open or a scheduled release, when fifteen minutes covers most of the move.
- Any intraday timing decision, where the current price is the entire question.
- Fast-moving thin securities, where fifteen minutes can be a very large distance.
- Confirming whether a stop or an alert level has been reached.
Conversely, an entire fundamentals-based process can run on delayed data with no loss at all, because a filing does not become less true fifteen minutes later.
On this platform
Which surfaces are real time and which are delayed depends on the products held. The members guide sets it out surface by surface.
What your plan carries — for membersWhat a delay is not
A delayed feed is not a lower-quality feed. Every print is the real print, at the real price, in the real sequence. The only difference is when it is released, and fifteen minutes later the delayed feed contains exactly what the real-time feed contained fifteen minutes earlier.
- Yesterday's chart is identical on both. Historical bars are historical bars.
- Fundamentals, filings and corporate actions are unaffected, because none of them are market data.
- The shape of a completed bar is the same. A delayed daily chart after the close is the same chart.
- Levels, ranges and every indicator computed over completed bars are identical.
What a delay costs is answers to questions about now: whether price is through a level at this moment, what the spread currently is, and what is happening in the minutes around an open or a release. Those are the only questions it touches, and they are a small part of what a chart is used for.
The corollary is that the delay's cost scales with how short the intended holding period is. Over minutes it is disqualifying. Over a week it moves an entry price slightly. Over a year it is not measurable.
Snapshot, streaming and how often a number changes
There is a second distinction that is often confused with the delay, and it is separate from it. A streaming quote is pushed as it changes; a snapshot quote is fetched when something asks for it, typically on a timer. A snapshot fetched every thirty seconds is not delayed in the entitlement sense, and it is still up to thirty seconds old.
Both can be true at once, and the visible symptom is the same: a number on the screen that does not match a number somewhere else. Distinguishing them matters because they are fixed by different things. An entitlement delay is a contractual matter with the exchange; a refresh interval is an engineering choice about how much traffic a page generates.
| Symptom | Usually | How to tell |
|---|---|---|
| Consistently about a quarter of an hour behind | An entitlement delay | The gap is stable and roughly fifteen minutes |
| Behind by seconds, catching up in jumps | A refresh interval | The gap varies and closes completely at each update |
| Correct at the close, behind intraday | An entitlement delay | End-of-day data is usually distributed without one |
A third thing is sometimes mistaken for both: a quote that is genuinely current but comes from one venue rather than from the consolidated tape. On a thinly traded security the last print on one exchange can be minutes old simply because nothing has traded there, which is not a delay in either sense.