A break of structure (BOS) is price breaking a swing point in the trend's direction, confirming continuation; a change of character (CHoCH) is the first break against the trend, warning it may be reversing. Both are just ways of reading the sequence of swing highs and lows - the same market structure that underpins price action and smart money concepts.
Structure in one paragraph
An uptrend is a staircase of higher highs and higher lows; a downtrend is lower highs and lower lows. As long as each new swing extends the pattern, the trend is intact. The moment price fails to make a new extreme and instead breaks the last swing the other way, something has changed. Reading structure is simply tracking that staircase and noticing when a step is missed.
Why the distinction matters
Trading a BOS means trading with momentum - a continuation entry, the natural fit for a trend-following approach. Trading a CHoCH means anticipating a turn, which is higher risk but higher reward when it works. Confusing the two - treating a normal pullback as a reversal, or ignoring a genuine character change - is one of the most common structural mistakes traders make.
How to trade a change of character
A CHoCH on its own is an alert, not an entry. The lower-risk approach is to wait for the character change, then enter from a retracement into an order block or fair value gap in the new direction, with a stop beyond the swing that failed. That way a single false CHoCH costs you a small, defined loss rather than a chase into a trend that was never really turning.
Important: what counts as a "valid" swing point is a judgment call, and different swing definitions produce different structure reads. Fix your rule - a minimum swing size, or a specific number of candles - before you test, or your backtest will quietly bend to fit whatever you hoped to see.
Backtest structure with the future hidden
Structure looks obvious in hindsight and murky in real time, which is exactly why you should test it bar by bar. In a simulator you mark swings as they form and act on each BOS or CHoCH before you know the outcome, so the failed signals count too. The expectancy over a proper sample tells you whether your structure reading is an edge or just a story.
BOS and CHoCH FAQ
What is the difference between BOS and CHoCH?
BOS breaks a swing point with the trend, confirming continuation; CHoCH is the first break against the trend, warning of a possible reversal.
How do I identify market structure?
Mark swing highs and lows: higher highs and higher lows is an uptrend, lower highs and lower lows a downtrend. Structure breaks when a swing point is taken out.
How do I trade a change of character?
Use the CHoCH as an early reversal signal, then enter from an order block or fair value gap in the new direction with a stop beyond the failed swing - and backtest it.