What Is a Killzone? ICT’s Session Windows, Explained
Ask five sources for the London killzone hours and you’ll get at least three different answers. 2:00–5:00 AM New York time. 7:00–10:00 UTC. “The first two hours after the London open.” Some include the pre-open; some don’t. Daylight saving shifts everything twice a year, and half the charts you’ll find online don’t say which convention they’re using.
That disagreement isn’t a reason to dismiss the concept. It’s a reason to understand what a killzone actually is — because once you do, the exact minutes matter a lot less than most explainers suggest.
Where the term comes from
“Killzone” comes from the teaching of the Inner Circle Trader (ICT), Michael J. Huddleston, whose framework we’ve covered before in the context of Power of Three. In that teaching, a killzone is a window of time around a major session open — Asia, London, New York — during which institutional participation is concentrated and the day’s meaningful price movement is disproportionately likely to begin.
That’s the whole idea. A killzone is not an indicator, not a signal, and not a prediction. It’s a time filter: a claim about when the market tends to be worth watching, not about what it will do.
The windows, as commonly taught
The most commonly taught set, expressed in New York time, looks roughly like this: an Asian killzone in the evening (around 8:00 PM–12:00 AM), a London killzone in the early morning (around 2:00–5:00 AM), a New York killzone mid-morning (around 7:00–9:00 or 8:30–11:00, depending on the source), and a London close window early afternoon. We’re deliberately writing “around”: published sources genuinely differ on the exact boundaries, and ICT’s own materials have presented variations over the years.
If the exact minutes were the mechanism, that variation would be a fatal problem. It isn’t — because the mechanism is the session open itself.
Why the windows exist at all
Strip away the terminology and the killzone concept rests on something measurable: trading activity is not evenly distributed across the day. The BIS Triennial Survey (April 2025) puts the United Kingdom at roughly 38% of global FX turnover and the United States at about 19% — so the hours when London and New York desks are active, and especially the hours when both are active at once, concentrate a large share of the day’s real participation.
A killzone is a rough map of those concentration windows. The reason “2:00–5:00 AM ET” keeps appearing in ICT materials isn’t that 2:00 AM is special — it’s that London opens then. Anchor to the session open in your own market’s convention and the DST headaches mostly resolve themselves.
What a killzone can and can’t tell you
What it can do: narrow your attention. If most of an instrument’s daily range tends to develop during specific hours, watching those hours beats watching all twenty-four. It also gives structure to other session-based observations — an Asian range that gets taken out during the London window is a more interesting event than the same move at 3:00 PM Singapore time.
What it can’t do: tell you direction, or guarantee that anything happens at all. Plenty of London windows chop sideways. There is, to our knowledge, no published, methodologically transparent study validating specific killzone boundaries as statistically privileged — and the precise-sounding win rates attached to killzone strategies in various corners of the internet come with no methodology attached. We treat those the way we treat all unsourced performance numbers: as marketing until proven otherwise.
A killzone is best understood as a taught convention with a real mechanism underneath it. The mechanism — concentrated session participation — is sourced and solid. The specific minute boundaries are convention.
Where this gets tedious by hand
Marking session windows manually means redrawing boxes across timezones, adjusting for DST twice a year, and keeping conventions consistent across every chart you open. That bookkeeping is one of the things SSM IQ Price Action with Sessions and PO3 handles systematically — sessions, their opens, and the ranges they build, tracked as one consistent layer instead of hand-drawn rectangles.
Where this leaves you
Treat killzones as a scheduling tool, not a strategy. Know which session opens matter for your instrument, watch how it actually behaves inside those windows for a few weeks, and be suspicious of any source that sells exact minutes as the edge. The windows tell you when to pay attention. What you do with that attention is the actual work.
Sources: BIS Triennial Central Bank Survey, April 2025 (turnover shares, net-gross basis); ICT/Michael J. Huddleston (killzone framework — attributed teaching, not a validated statistical claim); session-time variants as published across ICT-derived educational materials, checked 2026-08-18.