Technical Analysis · Intermediate · 5 min
Session highs and lows
You can mark the high and low of a trading session, explain why later sessions often test them and read a break of them carefully.
Three sessions, one day
Currency markets trade around the clock on weekdays, as the forex chapter showed. But they are not equally busy all day. Activity shifts from Asia to London to New York, and the chart often changes character with it.
Each session leaves marks on the chart: its highest and lowest price. Many short-term traders watch these marks closely, because the next session often comes back to test them.
Each session leaves marks
The session high is the highest price of a trading session, the session low its lowest. In currency markets, traders usually split the day into the Asian, London and New York sessions. For exchanges, the session is simply the trading day.
Why do these levels matter?
- Orders gather there. Research on currency orders by Carol Osler found that stop-loss orders cluster just beyond obvious levels and take-profit orders at them. A session's high and low are among the most obvious levels on an intraday chart.
- Volume changes between sessions. The Bank for International Settlements' survey shows the United Kingdom as the largest foreign exchange trading center. When London opens, more traders and more volume arrive, and the quieter Asian range is often tested.
- Shared reference points. Many traders, algorithms and news reports refer to the previous session's high and low.
In the fictional chart of a currency pair in hourly candles, the Asian hours move between 1.0802 and 1.0832. The levels are marked as the Asia high and low.
What a test of these levels can look like:
- A break and follow-through: the price moves beyond the level and keeps going. The previous session's range was too small for the new participants.
- A break and return: the price pokes beyond the level and quickly comes back inside. The orders beyond the level were filled, but no new move followed. The lesson on liquidity grabs covers this case.
London breaks the range
Follow the fictional day.
- Asia: for eight hours, the pair stays between 1.0802 and 1.0832, a range of 30 pips.
- London: in the second London hour, candle 10 rises to 1.0846 and closes at 1.0838, above the Asia high.
- New York: the pair moves between about 1.0832 and 1.0860 and reaches the day's high at 1.0860.
A pullback in the New York hours, on candle 17, stopped at 1.0832, exactly at the old Asia high, which now acted as support, as in the lesson on role reversal. A trader who had expected the Asian range to hold would have had a clear exit: a close above the Asia high. A trader trading the break had a reference for a stop back inside the range.
Common mistakes
- Treating session extremes as walls. They are reference points, not barriers.
- Ignoring time zones. Define sessions in one time zone and stick to it.
- Forgetting overlaps. London and New York overlap for several hours, often the busiest of the day.
- Assuming every break continues. Many reverse within the hour.
The takeaway
Each session leaves a high and a low. Later sessions often test them. A break is information, not a guarantee.
Check yourself
Quick quiz
4 questions. Instant feedback, nothing is saved.
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1Tap the candle that broke above the Asian session high.
Tap the chart.
Candle 10, in the London hours, rose to 1.0846 and closed at 1.0838, above the Asian high of 1.0832.
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2Why do later sessions often test the previous session's high or low?
Research on currency orders found that stop orders cluster just beyond obvious levels, which can draw the price toward them.
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3Which session usually sees the most foreign exchange trading?
The BIS survey shows the UK as the largest trading center. Activity often rises when London opens and when it overlaps with New York.
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4A session high breaks, but the price closes back below it within the hour. How do many traders read that?
Breaks of session extremes often fail. The lesson on liquidity grabs looks at this pattern.
of 4 correct.
Sources
- BIS: OTC foreign exchange turnover in April 2025 (turnover by trading center)
- Federal Reserve Bank of New York: Foreign Exchange Committee — about the FX market
- Osler: Currency orders and exchange rate dynamics — an explanation for the predictive success of technical analysis, Journal of Finance 58(5) (2003)