Bull Flag
A bull flag is a short continuation pattern: a steep, near-vertical advance (the pole) followed by a shallow pullback or sideways drift that slopes gently against the move (the flag). It reflects a pause in which early buyers take profits without new sellers taking control.
- Bias
- Bullish
- Category
- Chart Patterns
- Scan cadence
- Every close
What has to be true for a Bull Flag to trigger
- A steep, high-volume advance forming the pole
- A shallow consolidation that drifts against the direction of the pole
- The pullback retracing only part of the pole, since a deep retrace is a failed move rather than a flag
- Volume contracting through the flag relative to the pole
- The flag staying tight, without wide, erratic bars
How PatternGrade grades it
The grade rewards a strong, clean pole, a tight and shallow flag, and clear volume contraction during the pause. Wide bars, a deep retracement, or volume that stays elevated through the flag all pull the grade down.
Every scanner grades its hits A+, A or B from the pattern's own measurable structure. The grading is deterministic — the same chart always produces the same grade. It describes how closely the chart matches the pattern, not how likely anything is to happen; no hit rate or probability is attached to a grade. The reasoning is set out in the methodology.
What a Bull Flag looks like in practice
A stock gaps up on earnings and adds 25% over six sessions on volume three to four times its average. That is the pole. The next seven sessions drift down about 7%, each day's range tighter than the last, on volume that fades back to below average. The pullback holds well above the halfway point of the pole and the highs step gently lower. Two weeks, start to finish, with the flag portion taking most of it.
How a Bull Flag fails
A bull flag fails when the pullback stops being shallow. Retrace more than about half the pole and the pattern has lost its meaning. The buyers who drove the advance have been fully offset, and what looked like a pause is a reversal. The other failure is time: a flag that consolidates for six weeks instead of two has bled the momentum that made it worth watching, and usually resolves as a sideways range rather than a continuation. Volume expanding on the down days inside the flag is the earliest warning of both.
What this pattern is telling you
Bull flags are short-lived by nature. A flag that consolidates for too long stops being a flag and becomes a base. A flag that retraces most of its pole was never a flag at all.
PatternGrade is not a financial advisor and does not give buy or sell recommendations. Targets and stops shown on a pattern are reference levels derived from its geometry, not advice.
How to scan for Bull Flag setups
PatternGrade rescans every liquid US stock (~4,500 names) for this pattern after every close and returns the hits as a graded list, with the pattern drawn on each chart, so you review setups rather than hunt for them.
Join the waitlist to be invited when sign-ups reopen and see the current Bull Flag list, or browse all 75 patterns.
Bull Flag FAQ
How do I screen for bull flags?
PatternGrade's bull flag scanner runs against every liquid US stock after each close, so you get the night's flags as a graded list rather than flipping through charts.
How reliable is a bull flag?
It is one of the more consistent continuation patterns, but reliability depends heavily on the quality of the pole and the tightness of the flag, which is exactly what the A+/A/B grade separates.
How far should a bull flag pull back?
Ideally no more than a third of the pole, and rarely more than half. The point of the pattern is that the advance was barely given back: profit-taking without new selling. Once the retrace passes the halfway mark the structure reads as a failed move rather than a pause, which is why PatternGrade's grade drops sharply as retrace depth increases.
How long does a bull flag last?
Usually one to three weeks on daily bars. Flags are short by nature; the pattern describes a brief pause in an active move. A consolidation running past about four weeks has generally stopped being a flag, and is better read as a base.
Is a bull flag reliable?
It is one of the more consistent continuation patterns in a trending market and one of the least useful in a choppy one — which is true of continuation patterns generally. PatternGrade will not tell you how often it works — that is a performance claim, and the methodology page explains why none are published. What it does tell you is precisely which structural tests this chart passed.
What volume should a bull flag have?
Heavy on the pole, visibly lighter through the flag. That contraction is the pattern's core evidence: it says the pullback is drift rather than distribution. A flag forming on volume equal to or above the pole's is the main disqualifier, and it is weighted heavily in the grade.
Patterns a Bull Flag is mistaken for
- Pennant
- A flag's boundaries are roughly parallel: it is a channel drifting against the trend. A pennant's boundaries converge into an apex. Same pole, different consolidation shape.
- High Tight Flag
- A high tight flag requires a near-doubling in a matter of weeks and a very shallow consolidation. It is the rare, extreme version. Most flags do not qualify and should not be graded as if they did.
- Bear Flag
- Identical geometry, inverted: a sharp decline followed by a drift upward against it. The pole's direction is the only thing that separates them.
- Pullback to SMA
- A flag is defined by its relationship to the pole. A moving-average pullback is defined by where price lands. A shallow pullback can be both, but if there is no steep prior advance there is no flag.
Last reviewed . Structure and grading for the Bull Flag are reviewed against the scanner's own rules.