Why the London and New York Sessions Behave Differently

How the Asian, London and New York forex sessions differ in behaviour — not just hours: what drives each, where the volume is, what the London fix does at 16:00, and why late New York is the hour to be careful.

The hours of each session are on a table. What that table does not say is that the sessions behave differently: what moves the price, how much volume is behind it, and when the moves tend to reverse. This is the behavioural companion to global market trading hours.

Key Takeaways

• Asia establishes a range. London breaks it. New York decides whether the break holds.
• The London–New York overlap has the deepest liquidity of the day; the hours after London closes have the thinnest.
• Each session has its own data: Asia-Pacific releases, European releases, US releases. The pair's currencies decide which matter.
• 16:00 London is the daily benchmark fix, and flows cluster around it.

The Asian Session (roughly 00:00–09:00 UTC)

Tokyo, with Sydney before it and Singapore and Hong Kong alongside. Volume is a fraction of London's, and major pairs often spend the session in a range while JPY, AUD and NZD pairs take their cues from regional data and Asian equity markets. Ranges built here are frequently what London trades against.

The London Session (roughly 07:00–16:00 UTC)

The deepest session by turnover. European data lands in the first hours; EUR and GBP pairs are most active; and the first hour is often where the Asian range breaks, as European desks position on overnight news.

Two features matter for behaviour. The open is a burst of volume that can reverse the Asian direction within minutes. The 16:00 London fix — the WM/Refinitiv benchmark rate — attracts large flows from funds and corporates executing at the benchmark, which can produce sharp moves in the minutes either side of 16:00 that have nothing to do with news.

The New York Session (roughly 12:00–21:00 UTC)

US data at 13:30 UTC — employment, inflation, growth — is the most volatile scheduled moment of most trading days. The first four hours overlap with London and carry the day's peak liquidity; spreads on majors are tightest here. After London closes at 16:00 UTC, volume falls away steadily, and the last hours before the New York close are among the thinnest of the day: wider spreads, more slippage, and moves that are as likely to be positioning as information.

How They Interact

Worked Example: One Day on EURUSD

• 02:00 UTC — Asia holds a 30-pip range around 1.0850.
• 07:15 — London opens; a European survey beats forecast; EURUSD breaks the range high.
• 13:30 — US inflation data prints hotter than expected; the dollar rallies; EURUSD gives back the London move in twenty minutes.
• 16:00 — fix flows push it another 15 pips lower.
• 20:30 — spread widens from 0.9 to 2.4 pips; price drifts on small orders.

Same pair, one day, four different markets. A stop placed inside the Asian range at 02:00 was reasonable; the same stop distance at 13:30 was inside the noise. See volatility and liquidity.

(Illustrative. Times are approximate and shift with daylight saving.)

Why It Matters

Cost, noise and the reliability of a move all change by session. A trader who treats 02:00 and 13:30 as the same market is using one stop distance and one size for two different instruments. The practical habits: know which session is open and which data is due; expect the London open and the US data window to reverse what came before; and be sceptical of moves in the last two hours of New York. Building a consistent trading routine is largely about matching activity to these windows.

What is the best session to trade forex?

For major pairs, the London–New York overlap has the tightest spreads and the deepest liquidity. "Best" otherwise depends on the pair and the approach.

Why does the market reverse at the London open?

European desks position on overnight news with volume that Asia did not have. The Asian range is often the first thing that volume tests.

What is the London fix?

A daily benchmark exchange rate set at 16:00 London time. Large flows executed at the benchmark cluster around it, which can move prices without news.

Is the Asian session worth trading?

It is quieter and thinner for major pairs. JPY, AUD and NZD pairs are most active. Ranges built here often matter later in the day.

Why is late New York risky?

Volume is thin after London closes. Spreads widen and small orders move the price, so moves are less reliable and fills are worse.

Related Reading

Global market trading hours · Volatility and liquidity · Spread · Slippage · How to use an economic calendar