Forex Trading Sessions Explained: When Should Your EA Trade?

The forex market runs 24 hours a day, 5 days a week — but not all hours are equal. Understanding trading sessions is crucial for EA profitability because volatility, liquidity, spread width, and trend behavior change dramatically throughout the day. A strategy that's profitable during the London session might lose money during Asia. Getting session timing right is one of the simplest and most impactful optimizations you can make to any Expert Advisor.

The Four Major Sessions

Sydney Session (22:00 - 07:00 GMT)

The trading day begins in Sydney. This is the quietest session with the lowest volume in the forex market. AUD, NZD, and JPY pairs are most active, but even these trade at a fraction of London session volume. Price movements are typically small and range-bound — the market is "sleeping."

Best EA types: Range-trading, mean-reversion on AUD and NZD pairs. Some scalping strategies work during this session because of the predictable range behavior.

Avoid: Trend-following strategies — there simply isn't enough volume and momentum to sustain trends. Spreads can also widen significantly on non-AUD pairs.

Tokyo Session (00:00 - 09:00 GMT)

The Tokyo session overlaps with Sydney and adds significant volume, especially for JPY pairs. USD/JPY, EUR/JPY, and AUD/JPY see their highest activity. Price action during Tokyo tends to be smoother than during London, with fewer false breakouts and more predictable ranges.

Importantly, the Tokyo session creates the "Asian range" — the consolidation zone that many breakout strategies use as a setup for the London open.

Best EA types: Trend-following on JPY pairs, range-building for breakout setups, mean-reversion strategies.

London Session (08:00 - 17:00 GMT)

The busiest session in forex, accounting for approximately 35% of daily global forex volume. All European and GBP pairs see their highest activity, but EUR/USD and GBP/USD volume is massive. This session sets the daily direction for most major pairs. Spreads are at their absolute tightest.

The first hour of London (08:00-09:00 GMT) is particularly important. This is when the Asian range breakout occurs — European institutional traders enter the market and push price out of the overnight consolidation.

Best EA types: All types — trend-following, breakout, momentum, and even mean-reversion strategies. If you had to choose one session for your EA, this is it. The combination of high volume, tight spreads, and strong directional moves creates the most opportunity.

New York Session (13:00 - 22:00 GMT)

The second-busiest session, especially during the London/New York overlap (13:00-17:00 GMT). USD pairs see their highest activity. Major economic releases — NFP (first Friday of each month), CPI, Fed interest rate decisions — happen during this session and can create explosive moves.

After London closes (17:00 GMT), New York volume gradually decreases. The 17:00-22:00 window is similar to Asia in terms of reduced volatility and range behavior.

Best EA types: Trend-continuation during the overlap, momentum strategies around news releases. Late NY (after 17:00) suits mean-reversion approaches.

The London/New York Overlap: The Golden Window

The period from 13:00 to 17:00 GMT is the most liquid and volatile window of the entire trading day. Both London and New York traders are active simultaneously, creating the highest combined volume. This 4-hour window often produces:

The largest moves of the day
The tightest spreads on major pairs
The most reliable trend continuation
The best execution quality (minimal slippage)

If you can only trade one session, this is it. Many professional EAs trade exclusively during this window. In AlgoStudio, use the "London/NY Overlap" timing block or set custom hours (13:00-17:00 GMT) to target this period.

Session Comparison Table

Session	Hours (GMT)	Volume	Volatility	Best Pairs
Sydney	22:00-07:00	Low	Low	AUD/USD, NZD/USD
Tokyo	00:00-09:00	Medium	Low-Medium	USD/JPY, EUR/JPY
London	08:00-17:00	High	High	EUR/USD, GBP/USD, all majors
NY Overlap	13:00-17:00	Highest	Highest	EUR/USD, GBP/USD, USD/JPY
New York	13:00-22:00	High	Medium-High	USD pairs

Session-Based EA Strategies

Asian Range Breakout

One of the most popular and well-documented session-based strategies in forex:

During the Tokyo session (00:00-08:00 GMT), price consolidates in a narrow range — the "Asian range"
At the London open (08:00 GMT), European institutional traders enter and push price out of this range
Trade the breakout direction with a stop loss inside the range
Limit entries to the first 4 hours of London (08:00-12:00 GMT) for highest conviction breakouts

This strategy works because the transition from low volatility (Asia) to high volatility (London) is one of the most predictable patterns in forex. Our Breakout EA template implements this exact approach with ATR-based stops and range size filters.

London Close Strategy

Near the end of the London session (around 16:00-17:00 GMT), institutional traders close their intraday positions. This unwinding can create a reversal of the day's trend — price that moved up during London often pulls back as positions are liquidated. Mean-reversion EAs can profit from this predictable pattern.

Session Momentum Strategy

Trade in the direction established during the first 2 hours of the London session. If London opens bullish (price above the Asian close), look for buy setups. If bearish, look for sells. The first 2 hours often set the tone for the rest of the day.

News Avoidance

Major news releases (NFP, interest rate decisions, CPI data) create unpredictable spikes that can trigger stop losses in both directions within seconds. Many professional EAs add a rule: no new trades 30 minutes before and after high-impact news events. MT5's built-in economic calendar makes this filterable programmatically.

Which Session Should Your EA Trade?

EA Type	Best Session	Why
Trend-following (MA crossover)	London, NY Overlap	Strongest trends, highest momentum, institutional flow
Mean-reversion (RSI)	London, Late NY	Clear overbought/oversold levels with enough liquidity for execution
Breakout (Asian range)	London Open (08:00-12:00)	Volatility expansion from Asian consolidation
Scalping	London, NY Overlap	Tightest spreads, highest liquidity, fastest execution

Common Session Timing Mistakes

Trading 24/5 Without Session Filters

Running your EA around the clock sounds efficient but usually hurts performance. Signals generated during low-volume sessions (late NY, early Sydney) have wider spreads, more slippage, and less follow-through. Adding a session filter that limits trading to London hours typically improves profit factor by 20-40%.

Ignoring Timezone Differences

Your broker's server time may not be GMT. If your broker uses EET (GMT+2), "08:00" in your EA code means 06:00 GMT — you'd be trading before London opens. Always verify your broker's timezone offset and adjust accordingly.

Not Accounting for DST

Daylight Saving Time shifts session boundaries by 1 hour twice a year. US and UK DST changes happen on different dates, which can temporarily shift the overlap window. Account for this in your EA or use GMT-based timing that doesn't change.

Configuring Sessions in AlgoStudio

AlgoStudio makes session-based trading easy. Drag a Trading Sessions block from the timing category and select your preferred session. For custom hours, use the Custom Times block where you can set exact start/end times and trading days.

You can also combine multiple timing blocks — for example, trade during both the London open (08:00-12:00) AND the NY overlap (13:00-17:00) while skipping the quiet midday period.