3 Tier London Breakout Indicator: Three Bar Channels

Written by Dominic Walsh · Published 21 May 2026 · Last updated 9 Sep 2026

The 3 tier london breakout indicator draws three rolling channels at once. `Tier1Bars`, `Tier2Bars` and `Tier3Bars` set them at 12, 24 and 48 bars. On M15 those spans work out at three, six and twelve hours, which is why the defaults suit a London session chart. Only the widest tier triggers a mark.

This build ships as a compiled .ex4 for MT4 and .ex5 for MT5; the screenshots below come from GBPUSD M15.

Platforms	MT4 (.ex4) + MT5 (.ex5)
Chart window	Main price chart
Plots	8: T1 Hi, T1 Lo, T2 Hi, T2 Lo, T3 Hi, T3 Lo, Buy Break, Sell Break
Alerts	popup, push notification, email, sound
Inputs	10

What the 3 Tier London Breakout Indicator draws on the chart

T1 Hi and T1 Lo are the yellow lines, the tightest pair.

T2 Hi and T2 Lo are the orange pair covering twice the span.

T3 Hi and T3 Lo are the dodger blue pair and the only tier that fires a signal.

Buy Break and Sell Break place lime and red arrows `ArrowOffsetPoints` from the bar.

• T1 Hi: line, yellow, width 1
• T1 Lo: line, yellow, width 1
• T2 Hi: line, orange, width 2
• T2 Lo: line, orange, width 2
• T3 Hi: line, dodger blue, width 3
• T3 Lo: line, dodger blue, width 3
• Buy Break: arrow, lime, width 4, arrow code 233
• Sell Break: arrow, red, width 4, arrow code 234

How the 3 Tier London Breakout Indicator calculates its values

Building three rolling channels

HighN and LowN scan back `Tier1Bars` `12`, `Tier2Bars` `24` and `Tier3Bars` `48` bars from the current one. Each pair of buffers then holds the highest high and the lowest low over its own span. Three spans on one chart show you how the range nests inside itself.

Testing the outer channel

A buy needs the previous close at or below the previous T3 Hi and the current close above that same level. The sell case mirrors it against T3 Lo. Comparing against the earlier bar value stops the channel moving under the test as the break happens.

What the tier spans mean in hours

The code counts bars, not clock time, so the timeframe decides the span. On M15 the three tiers cover three, six and twelve hours. On M5 they cover one, two and four. Choose the chart period so `Tier3Bars` lands near the stretch you actually care about.

How to read the signals

The three channels nesting tightly means the range has been steady across all spans.

T1 pressing against T3 means the recent range now fills the wider one.

Only a close through T3 produces a mark, so the inner tiers are context.

A break with the tiers already stacked reads differently from one out of a tight coil.

Alert channels in this build: popup, push notification, email and sound, one message per closed bar.

`EnableAlerts` ships on with `EnablePopup` carrying the message. `EnablePushNotify`, `EnableEmail` and `EnableSound` are off by default, and `SoundFile` names the clip. The guard allows one message per closed bar.

Every 3 Tier London Breakout Indicator input

Core settings

Setting	What it does	Default
Tier1Bars	Span of the tightest channel, default `12`.	12
Tier2Bars	Span of the middle channel, default `24`.	24
Tier3Bars	Span of the outer channel, default `48`. This is the only tier that triggers a mark.	48

Display settings

Setting	What it does	Default
ArrowOffsetPoints	Distance in points between a break arrow and the candle, default `40`.	40

Alert settings

Setting	What it does	Default
EnableAlerts	master toggle. Switches the whole alert block on, default `true`.	on
EnablePopup	MT4 popup dialog. Shows the MT4 dialog on a tier three break, default `true`.	on
EnablePushNotify	mobile MT4 push notification. Sends the break to the MetaTrader mobile app, default `false`.	off
EnableEmail	SMTP email (configure in MT4 Tools > Options > Email). Mails the break through the terminal SMTP settings, default `false`.	off
EnableSound	play sound file from MT4/Sounds/. Plays a file from the Sounds folder on a break, default `false`.	off
SoundFile	Name of the wav file the sound channel uses, default `alert.wav`.	alert.wav

Settings that fit your chart

GBPUSD M15 is the reference chart, and the defaults were sized for it. Twelve hours of range in `Tier3Bars` covers the Asian session and the London open together. On M5 the same numbers shrink to four hours, which suits a tighter breakout style. On H1 the outer tier stretches across two days.

When the 3 Tier London Breakout Indicator fails

The code counts bars and never reads the clock, so it cannot know when London actually opens.

A channel break in a quiet range reverses as often as it continues.

The inner tiers carry no logic at all. They are there to show context, not to filter.

Copy the compiled 3 Tier London Breakout Indicator file into your MQL4/Indicators folder, and the MT5 build into MQL5/Indicators, then restart the terminal and drag it onto a chart. The step-by-step guide with screenshots is at how to install MT4 and MT5 indicators.

Related on forexmt4systems.com: London Session Breakout Strategy.

Download the 3 Tier London Breakout Indicator for MT4 and MT5

The zip holds the compiled 3 Tier London Breakout Indicator build for MT4 and MT5, plus a short README. Compiled files only, no source. Enter your email below and the download link arrives in your inbox.

FAQ

Does the tool detect the London session by clock?

No, and it is worth being clear about that. It counts bars only. `Tier3Bars` at `48` happens to cover twelve hours on M15, which lines up with the stretch traders watch around the London open. Change the chart period and that alignment goes away.

Why does only Tier3Bars trigger a mark?

Because a break of the widest channel is the least common of the three. T1 and T2 would fire constantly at 12 and 24 bars. Leaving them as lines gives you the nesting picture without flooding the chart with arrows that mean very little.

What do the T1 Hi and T1 Lo lines add?

Context about how the range is built. When the yellow pair sits well inside the blue pair, recent trade has been narrow relative to the wider span. When all three converge, the market has been going nowhere on every timescale the tool measures.

Do the defaults suit GBPUSD M15?

They were chosen for it. GBPUSD moves enough around the London open for a twelve-hour channel to matter, and M15 gives enough bars for the tiers to separate. On a quieter pair the same settings produce fewer breaks and more time inside the channels.

Are results guaranteed?

No. Trading involves risk. Results are not guaranteed; past performance is not indicative of future results. Use the 3 Tier London Breakout Indicator as one input. Always backtest before trading live.