Gap Trading Basics: Breakaway, Exhaustion, and Gap Fill
Understand stock market gaps, why they happen, when gaps fill, and how beginners should practice them safely.
· 5 min read · gap, stocks, volatility, day-trading
A gap happens when a market opens at a different price from the previous close. Stocks gap because news, earnings, analyst changes, macro events, or overnight order flow resets expectations while the regular session is closed.
Three common gap types
Breakaway gaps leave a range with strong participation. Continuation gaps appear in the middle of a trend. Exhaustion gaps happen late, after everyone has already chased. The type depends on context, not the size of the gap alone.
Gap fill is a tendency, not a law
Price breakout accompanied by a volume spike several times the average, visually confirming the move.
A gap fill means price returns to the prior close. Some gaps fill quickly; others never do. A gap with strong volume and trend alignment is less likely to fill immediately than a weak gap into resistance.
Beginner rule: wait for the first range
The opening minutes are noisy. Let the first range form, mark high and low, then judge whether price accepts above, rejects below, or rotates inside. Trading the first print is usually emotion, not analysis.
Common mistakes
Assuming every gap will fill. Trading the open print on emotion. Not adjusting position size for the wider overnight range.
- Assuming every gap will fill — some gaps, especially breakaway gaps, never fill and the trade goes against you indefinitely.
- Trading the first print of the open on emotion — the bid-ask spread is widest and price is most manipulated right at the open.
- Not adjusting position size for the wider overnight range — gap days have larger ATR, which means stops must be wider too.
Practice opening range decisions →
This article was written and reviewed by the founder. AI tools may assist with drafting; every fact, figure, and example is verified by the author before publishing.