Session Box Indicator: Asia, London and New York Ranges

Written by Dominic Walsh · Published 8 Jul 2026 · Last updated 26 Aug 2026

The session box indicator draws a box around each trading session as it builds. Asia, London and New York each get their own hours and colour. Once a session range is set, Session Break Up and Session Break Down mark the first close that leaves it.

This build ships as a compiled .ex4 for MT4 and .ex5 for MT5.

Platforms	MT4 (.ex4) + MT5 (.ex5)
Chart window	Main price chart
Plots	2: Session Break Up, Session Break Down
Alerts	popup, push notification, email, sound
Inputs	21

What the Session Box Indicator draws on the chart

A rectangle object tracks each session, stretching as new highs and lows print inside its hours.

Session Break Up marks the first close above a session high.

Session Break Down marks the first close below a session low.

Each session carries its own colour, so overlapping hours stay readable.

• Session Break Up: arrow, lime, width 2, arrow code 233
• Session Break Down: arrow, red, width 2, arrow code 234

How the Session Box Indicator calculates its values

Defining a session

Each session has a start hour and an end hour, and a bar belongs to it when its hour falls at or after the start and before the end. That means the end hour itself sits outside the session.

London and New York overlap by design at the defaults, since the real markets do. Both boxes build at once through those hours.

Building the range

The first bar inside a session seeds its high and low. Every later bar in the same session widens the box if it prints a new extreme.

So the box grows as the session runs and only stops when the hours end. What you see mid session is a partial range, not a finished one.

Marking the break

Once a range exists, the code watches for a close beyond either edge and marks the first one on each side.

A latch stops it marking again, so a session that keeps pushing higher gives one marker rather than a run of them.

How to read the signals

A tall box means the session traded a wide range, which says more about conditions than direction.

The London and New York boxes overlap at the defaults, and price inside both belongs to whichever range you are trading.

A break marker fires once per side per session, so the absence of one does not mean price stayed inside.

Session hours run on your broker clock, not on local market time.

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

Alerts cover popup, push, email and sound on the first break of a session range. A bar time check keeps it to one alert per closed bar.

Every Session Box Indicator input

Core settings

Setting	What it does	Default
AsiaStartHour	Asia session open hour. AsiaStartHour opens the Asian box at hour 0 by default, on broker time.	0
AsiaEndHour	Asia session close hour. AsiaEndHour closes it at 8. The end hour itself falls outside the session.	8
LondonStartHour	London session open hour. LondonStartHour opens the London box at 8, picking up where Asia ends.	8
LondonEndHour	London session close hour. LondonEndHour closes it at 16.	16
NYStartHour	New York session open hour. NYStartHour opens New York at 13, deliberately overlapping London.	13
NYEndHour	New York session close hour. NYEndHour closes it at 22.	22

Display settings

Setting	What it does	Default
ShowAsia	ShowAsia draws the Asian box and defaults to true. The London and New York switches work the same way.	on
ShowLondon	(see inputs panel)	on
ShowNewYork	(see inputs panel)	on
AsiaColor	(see inputs panel)	gold
LondonColor	(see inputs panel)	dodger blue
NYColor	(see inputs panel)	tomato
BoxWidth	(see inputs panel)	1
ArrowGapPips	arrow offset from candle.	8.0
HistoryDays	limit drawn boxes to recent days.	30

Alert settings

Setting	What it does	Default
EnableAlerts	(see inputs panel)	on
EnablePopup	(see inputs panel)	on
EnablePushNotify	(see inputs panel)	off
EnableEmail	(see inputs panel)	off
EnableSound	(see inputs panel)	off
SoundFile	(see inputs panel)	alert.wav

Settings that fit your chart

This build ships with no recommended chart. Session boxes only mean something intraday, so M5 through H1 is the natural home. On H4 a session holds a couple of bars and the box stops describing a range. On daily charts sessions disappear inside each candle entirely.

When the Session Box Indicator fails

Hours come from the broker clock, so a server in a different timezone shifts every box. Check what your broker calls midnight before trusting the defaults.

Daylight saving moves the real sessions while these fixed hours stay put, which drifts the boxes twice a year.

A break marker fires once per side, so a second push through the same edge goes unmarked.

The box you watch mid session is incomplete, and its range can widen after you have acted on it.

Copy the compiled Session Box 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.

Background reading on the method behind the Session Box Indicator: the foreign exchange market at Britannica, Registered share on Wikipedia.

Download the Session Box Indicator for MT4 and MT5

The zip holds the compiled Session Box 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

Why do LondonEndHour and NYStartHour overlap?

Because the markets do. LondonStartHour is 8 and LondonEndHour is 16, while NYStartHour is 13, so three hours carry both. That overlap is the busiest stretch of the day for most majors, and seeing both ranges at once is the point of drawing them separately.

Does AsiaEndHour 8 include hour 8 in the Asian box?

No. A bar belongs to a session when its hour is at or after the start and strictly before the end, so hour 8 falls outside Asia and inside London. That is what lets the two sit back to back without double counting a bar.

Will a Session Break Up marker appear twice in one session?

No. A latch records that the upper side has already fired and blocks any repeat for that session. If price pushes through, pulls back and pushes again, only the first close beyond the high gets marked.

Does AsiaStartHour adjust for daylight saving?

They do not. The start and end hours are fixed numbers on your broker clock, so when the real sessions shift an hour the boxes stay where they are. Adjusting the hours by hand twice a year keeps them aligned.

Are results guaranteed?

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