Skip to content

Break of Structure (BOS)

OVERVIEW

A break of structure (BOS) occurs when price closes beyond the most recent significant swing high (in an uptrend) or swing low (in a downtrend), confirming that the existing trend is intact and extending. BOS is the core trend-continuation signal in Smart Money Concepts (SMC) and price-action trading. It is distinct from a change of character (CHoCH), which signals a trend reversal — a BOS confirms the trend you already have, while a CHoCH is the first sign that trend is ending.

HOW TO USE

Identifying a Break of Structure

Follow these three steps to confirm a valid BOS:

  1. Mark the most recent swing high and swing low. A swing high is a candle whose high exceeds the highs of the candles immediately before and after it. The inverse applies for swing lows.

  2. Determine current trend direction. Higher highs and higher lows indicate an uptrend. Lower highs and lower lows indicate a downtrend.

  3. Wait for a candle close beyond the relevant swing point. In an uptrend, a candle must close above the prior swing high. In a downtrend, a candle must close below the prior swing low. Wicks through the level without a body close do not count — that is a liquidity sweep, not a BOS.

BOS Formula

Condition BOS Value
Close > PriorSwingHigh (uptrend) 1 — BOS confirmed
Close < PriorSwingLow (downtrend) 1 — BOS confirmed
Neither condition met 0 — No BOS

FEATURES

Three Core Trading Applications

Use Case Description
Trend Confirmation Only take long entries after a bullish BOS confirms the uptrend is intact. Avoid counter-trend positions until a CHoCH invalidates the structure.
Entry Trigger Enter on the close of the breaking candle or wait for a retest of the broken level, where former resistance becomes support.
Stop Placement Place stops below the most recent higher low in uptrends, or above the most recent lower high in downtrends, for structure-defined risk.

Displacement Filter

Traders often require the breaking candle to display displacement — a large body relative to the recent average candle range — to filter out weak or low-conviction breaks.

Algorithmic Use

BOS functions as a pre-filter in momentum systems. Many algorithms require a confirmed BOS on the 1H or 4H timeframe before triggering entries on lower timeframes.

WORKED EXAMPLE

The following example illustrates a confirmed bullish BOS on a 1-hour chart.

Parameter Value
Asset TSLA
Timeframe 1-hour
Prior swing high $287.40 (set May 9, 2026)
Pullback low $278.10 (May 11, 2026)
BOS candle close $289.85 at 1:00 PM ET, May 12, 2026
Subsequent extension $296.20 over the next two sessions

The candle close at $289.85 cleared the $287.40 swing high, confirming trend continuation. Price extended to $296.20, validating the signal.

LIMITATIONS AND COMMON MISCONCEPTIONS

Misconception Reality
Entering immediately on the BOS candle is optimal The BOS candle is often the worst-priced entry. Waiting for a retest of the broken level improves risk-reward.
A 5-minute BOS is actionable on its own BOS is timeframe-dependent. A lower-timeframe BOS is unreliable if the higher-timeframe trend is opposite. Multi-timeframe alignment is required.
A wick above the swing high is a BOS A wick spike without a body close is a stop run, not a BOS. No structure has broken without a confirmed close.

A BOS confirms the existing trend, but it does not predict how far the trend will extend.