A price gap on a chart appears when a security opens at a price meaningfully different from its previous close, with no trading in between. Gaps are visually distinctive and analytically informative in ways that continuous price movement is not. Understanding the four common gap types — and what each historically implies — provides one of the more useful pattern-recognition tools in technical analysis.

What a gap actually represents

A gap describes a specific market condition: information or sentiment arrived between the previous close and the current open that shifted the market's equilibrium enough that no participant was willing to trade at the intermediate prices. The size of the gap describes the magnitude of the shift.

Gaps are more common on individual stocks (which trade only during specific hours) than on continuously-traded instruments (futures, cryptocurrency). They occur most commonly at overnight sessions, weekends, and after specific news events.

The four gap types

Traditional technical analysis identifies four broad gap types with different characteristic patterns.

Common gaps. Small gaps that occur during ordinary trading with no specific news catalyst. Usually filled (the price returns to trade through the gap zone) within a short period. Carry limited analytical information — they typically reflect ordinary noise in market pricing rather than any specific shift.

Breakaway gaps. Gaps that occur at the start of significant new price movements, breaking out of consolidation patterns or through significant support/resistance levels. Often accompanied by high volume. Carry more analytical weight because they mark specific shifts in market character.

Continuation gaps. Gaps that occur during established trends, marking acceleration in the direction of the existing move. Typically appear roughly in the middle of larger moves and can help identify the strength of a trend that is already in place. Also called "runaway gaps" or "measuring gaps" because they sometimes appear at approximately the midpoint of complete moves.

Exhaustion gaps. Gaps that occur late in extended moves, often on high volume, marking the final push before a reversal. Distinguishing exhaustion gaps from continuation gaps in real time is difficult; the two often look similar as they form and can only be reliably identified after the subsequent price action develops.

The gap-fill pattern

One of the most-cited patterns in gap analysis is the tendency of gaps to be "filled" — meaning subsequent trading returns to the gap zone and closes the gap left in the chart.

The empirical evidence for gap-fill behaviour is mixed. Common gaps do frequently get filled quickly. Breakaway and continuation gaps often do not get filled for long periods (sometimes never, if they mark durable trend shifts). Exhaustion gaps typically get filled during the subsequent reversal.

Using "gaps get filled" as a mechanical decision rule produces mediocre results. The pattern applies to some gap types more than others, and identifying the gap type in real time is difficult.

Volume as a distinguishing factor

Volume accompanying the gap provides some information about which type of gap it likely is.

High-volume gaps at meaningful chart levels are more likely to be breakaway gaps or continuation gaps. The high volume reflects specific investor conviction driving the price movement.

Low-volume gaps are more likely to be common gaps or thin-market artifacts. They often get filled quickly and carry limited analytical significance.

Very high volume on gaps in late trends can indicate exhaustion. The volume represents the last waves of participants entering positions before the trend reverses.

Volume alone does not definitively identify gap type, but it provides useful information when combined with the chart context.

The specific news-driven gaps

Many gaps have specific identifiable catalysts — earnings announcements, regulatory decisions, geopolitical events. These "news gaps" have their own patterns.

Post-earnings gaps in specific directions have been extensively studied. The empirical finding is that stocks often continue drifting in the direction of the post-earnings gap for weeks after the initial move — a pattern called "post-earnings-announcement drift" or PEAD. This has been one of the more consistently documented factor anomalies in equity markets.

News-driven gaps in individual stocks often reflect fundamental information that will affect the security for months. Fading such gaps (betting on quick reversal) has historically produced poor outcomes.

Time-frame considerations

Gaps on intraday charts (5-minute, hourly) have different implications than gaps on daily charts. Intraday gaps often reflect specific news moments or opening/closing microstructure effects, and their patterns differ from the daily-chart patterns described above.

Daily-chart gaps provide more useful analytical information. Weekly-chart gaps (where a week's opening price differs meaningfully from the previous week's close) can be even more significant, though they are less common.

The specific market context

Whether a gap is analytically meaningful depends on the specific market context.

Small-cap stocks with thin trading often show gaps that reflect microstructure effects rather than genuine information shifts. Reading these as signals typically produces poor results.

Large-cap stocks with heavy trading volume show gaps that more reliably reflect specific news or sentiment shifts. These gaps carry more analytical weight.

Highly volatile stocks (biotech, small-cap technology) show gaps as a regular part of normal trading. The specific pattern in each individual case matters more than the presence of gaps generally.

What gaps do not tell you

Gaps do not tell you the specific size or duration of subsequent moves. They describe the current shift but not what happens next.

Gaps do not tell you whether the current move is beginning, middle, or end. This must be inferred from broader context including trend structure, volume patterns, and fundamental developments.

Gaps do not guarantee any specific subsequent action. The tendency of some gap types to be filled is a probabilistic observation, not a rule.

The rule to internalise

Gaps are informative chart events that describe specific shifts in market conditions. Different gap types carry different information, and reading them requires understanding both the specific gap type and its broader chart context. Using gap patterns as mechanical decision rules typically produces mediocre results; using them as description of current conditions integrated with other analysis typically produces sharper interpretation of what the market is currently signalling. The distinction between the two uses is one of the more important skills in technical analysis.

Educational content only. Not investment advice.