The box
A fixed window before or across the session open — commonly the hour before London, or the first hour of it. Mark its high and low and do not adjust them afterwards. The window is fixed in advance precisely so that you cannot choose it later to suit the move you wish you had taken.
The break
A candle closing outside the box, with the stop placed on the opposite side of the box or a little beyond the breaking candle. The most common failure is entering the first poke outside on a wick, which is the same fakeout mechanism as everywhere else — waiting for the close removes most of it and costs a few pips.
One trade, then stop
One attempt a day, or at most two. Without this rule the method turns into trading the whole session, and the whole reason it works for people with jobs is that it occupies an hour and then ends. If the break fails and price returns into the box, the day is over — the second and third attempts are where the discipline goes and the losses accumulate.
Why a session open
Liquidity arrives at a session open: participants who were absent overnight start trading, and the range that formed while they were away gets resolved. That is a real reason and it is time-based, so it can be planned around, unlike a setup that might appear at any hour. The New York open works similarly; the overlap between London and New York is the busiest window of the day.
Where it fails
On a day with major news scheduled just after the open, the box means nothing — the news moves price and the range is irrelevant. Check the calendar before marking the box, and if there is a high-impact release in the window, skip the day. Skipping is a normal outcome of this strategy, not a failure to find a trade.
In short
| Box | A fixed window around a session open |
|---|---|
| Entry | A close outside the box |
| Stop | Opposite side of the box |
| Limit | One trade a day, two at most |
| Skip when | High-impact news falls in the window |
Common questions
Which session?
London for most pairs, New York for dollar pairs. Tokyo produces narrower ranges and more false breaks on the majors, so it suits the yen crosses better if it suits anything.
How long should the box be?
An hour is the usual choice. What matters far more is that you fix it once and never change it mid-week to fit what happened.
What if both sides break during the day?
That is a ranging day, and the one-trade rule is what stops it costing you four losses instead of one. Take the day off.
Trading forex and CFDs on margin carries a high level of risk. Most retail accounts lose money. Nothing on this page is financial advice or a recommendation to trade.