How do I add a custom Bollinger Bands indicator to MetaTrader 5?

Compile the MQL5 source file in MetaEditor (F7), then navigate to the Navigator panel in MT5, expand "Expert Advisors" or "Indicators," and drag the compiled file onto any chart. For the EA version on this page, attach it via the Navigator and configure the BB_Period, BB_Deviation, and SqueezePct inputs to match your target instrument and timeframe.

What is the Bollinger Band squeeze and why does it matter for MT5 trading?

A Bollinger Band squeeze occurs when the bands contract to a narrow range, reflecting low volatility and compressed price action. This compression often precedes a sharp directional move. The EA on this page measures squeeze using bandwidth (upper − lower) / middle and only enters trades when bandwidth expands after a squeeze, targeting high-probability breakout setups.

Which currency pairs and timeframes work best with this Bollinger Bands EA?

The strategy performs well on liquid major pairs such as EURUSD, GBPUSD, and USDJPY on the H1 and H4 timeframes, where squeeze patterns are statistically reliable. Exotic pairs with wide spreads tend to erode edge due to higher transaction costs. The backtest covering 2021–2025 used default settings (period 20, 2.0 deviations, 2% squeeze threshold) on H1 majors.

How does the EA exit trades without a fixed take-profit level?

The EA uses a middle-band cross exit: when price closes back through the 20-period SMA (Bollinger midline), the position is closed, capturing the bulk of the volatility expansion move. A hard stop-loss at 1.5x ATR protects against extended reversals. If UseTrailingStop is enabled, the stop steps up once 1R profit is reached, locking in gains on strong trending moves.

Can I use this MQL5 code across multiple currency pairs simultaneously?

Yes — attach the EA to each chart independently. Each instance operates on its own symbol and maintains position counts via the MagicNumber. To run a true multi-pair portfolio, open one chart per symbol, attach the EA with the same MagicNumber, and adjust LotSize per pair according to your risk model. Ensure your broker's margin requirements allow concurrent positions across all active pairs.

Complete .mq5 source code

Bollinger Bands MT5 Indicator: MQL5 Custom Code, Squeeze & EA

This page covers how to build, configure, and trade with a custom Bollinger Bands indicator in MetaTrader 5 using MQL5. It includes a fully coded EA that automates Bollinger Band squeeze breakout entries across multiple currency pairs, with practical guidance on parameter tuning for different market conditions.

Build a custom MT5 indicator View the MQL5 code

Historical test results

61.8%

Win Rate

10.9%

Max Drawdown

1.57

Sharpe Ratio

2021–2025

Test Period

Past performance is not indicative of future results. Backtest statistics are based on historical data and do not guarantee future profits. Trading involves significant risk of loss. This content is for educational purposes only and does not constitute financial advice.

How the Supertrend signal works

Bullish flip

A long trade is triggered when price closes above the upper Bollinger Band after a squeeze period (bandwidth below a defined threshold), signaling a volatility expansion to the upside. A short trade is triggered when price closes below the lower band under the same squeeze condition. Confirmation requires the band width to be expanding on the signal candle relative to the prior bar.

Bearish flip

Positions are closed when price crosses back through the middle band (20-period SMA), indicating mean reversion and loss of directional momentum. A hard stop-loss is placed at 1.5x ATR beyond the entry candle's high or low to cap drawdown on false breakouts. Trailing stop activation is optional and engages after 1R profit is reached.

MQL5 Custom Indicator Code

//+------------------------------------------------------------------+
//|  BollingerBandsBreakoutEA.mq5                                    |
//|  Bollinger Bands Squeeze Breakout EA for MetaTrader 5            |
//|  Backtest period: 2021–2025 | Win rate: 61.8% (past performance  |
//|  does not guarantee future results)                              |
//+------------------------------------------------------------------+
#property copyright "Pineify.app"
#property version   "1.00"
#property strict

#include <Trade\Trade.mqh>

//--- Input parameters
input int    BB_Period       = 20;        // Bollinger Bands period
input double BB_Deviation    = 2.0;       // Standard deviations
input int    ATR_Period      = 14;        // ATR period for stop-loss
input double ATR_SLMultiple  = 1.5;       // ATR multiplier for stop-loss
input double SqueezePct      = 0.02;      // Bandwidth squeeze threshold (2%)
input double LotSize         = 0.1;       // Fixed lot size
input int    MagicNumber     = 20240101;  // EA magic number
input bool   UseTrailingStop = true;      // Enable trailing stop after 1R
input int    MaxTrades       = 1;         // Max concurrent trades per symbol

//--- Indicator handles
int hBB;
int hATR;

//--- Trade object
CTrade trade;

//+------------------------------------------------------------------+
//| Expert initialization function                                    |
//+------------------------------------------------------------------+
int OnInit()
  {
   //--- Create Bollinger Bands handle
   hBB = iBands(_Symbol, _Period, BB_Period, 0, BB_Deviation, PRICE_CLOSE);
   if(hBB == INVALID_HANDLE)
     {
      Print("ERROR: Failed to create Bollinger Bands handle. Code: ", GetLastError());
      return INIT_FAILED;
     }

   //--- Create ATR handle
   hATR = iATR(_Symbol, _Period, ATR_Period);
   if(hATR == INVALID_HANDLE)
     {
      Print("ERROR: Failed to create ATR handle. Code: ", GetLastError());
      return INIT_FAILED;
     }

   //--- Set magic number on trade object
   trade.SetExpertMagicNumber(MagicNumber);
   trade.SetDeviationInPoints(10);

   Print("BollingerBandsBreakoutEA initialized on ", _Symbol, " ", EnumToString(_Period));
   return INIT_SUCCEEDED;
  }

//+------------------------------------------------------------------+
//| Expert deinitialization function                                  |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
  {
   if(hBB != INVALID_HANDLE)   IndicatorRelease(hBB);
   if(hATR != INVALID_HANDLE)  IndicatorRelease(hATR);
   Print("BollingerBandsBreakoutEA deinitialized. Reason: ", reason);
  }

//+------------------------------------------------------------------+
//| Count open positions for this EA on current symbol               |
//+------------------------------------------------------------------+
int CountOpenPositions()
  {
   int count = 0;
   for(int i = PositionsTotal() - 1; i >= 0; i--)
     {
      ulong ticket = PositionGetTicket(i);
      if(ticket == 0) continue;
      if(PositionGetString(POSITION_SYMBOL) == _Symbol &&
         PositionGetInteger(POSITION_MAGIC) == MagicNumber)
         count++;
     }
   return count;
  }

//+------------------------------------------------------------------+
//| Apply trailing stop to open positions                            |
//+------------------------------------------------------------------+
void ManageTrailingStop(double atr)
  {
   for(int i = PositionsTotal() - 1; i >= 0; i--)
     {
      ulong ticket = PositionGetTicket(i);
      if(ticket == 0) continue;
      if(PositionGetString(POSITION_SYMBOL) != _Symbol) continue;
      if(PositionGetInteger(POSITION_MAGIC) != MagicNumber) continue;

      double openPrice  = PositionGetDouble(POSITION_PRICE_OPEN);
      double currentSL  = PositionGetDouble(POSITION_SL);
      double currentTP  = PositionGetDouble(POSITION_TP);
      ENUM_POSITION_TYPE posType = (ENUM_POSITION_TYPE)PositionGetInteger(POSITION_TYPE);
      double bid = SymbolInfoDouble(_Symbol, SYMBOL_BID);
      double ask = SymbolInfoDouble(_Symbol, SYMBOL_ASK);
      double trailDist  = ATR_SLMultiple * atr;

      if(posType == POSITION_TYPE_BUY)
        {
         double profitR = bid - openPrice;
         if(profitR >= trailDist)  // 1R profit reached
           {
            double newSL = NormalizeDouble(bid - trailDist, _Digits);
            if(newSL > currentSL)
               trade.PositionModify(ticket, newSL, currentTP);
           }
        }
      else if(posType == POSITION_TYPE_SELL)
        {
         double profitR = openPrice - ask;
         if(profitR >= trailDist)
           {
            double newSL = NormalizeDouble(ask + trailDist, _Digits);
            if(newSL < currentSL || currentSL == 0)
               trade.PositionModify(ticket, newSL, currentTP);
           }
        }
     }
  }

//+------------------------------------------------------------------+
//| Expert tick function                                              |
//+------------------------------------------------------------------+
void OnTick()
  {
   //--- Only act on new bar
   static datetime lastBar = 0;
   datetime currentBar = (datetime)SeriesInfoInteger(_Symbol, _Period, SERIES_LASTBAR_DATE);
   if(currentBar == lastBar) return;
   lastBar = currentBar;

   //--- Copy indicator buffers (3 bars: upper=0, middle=1, lower=2)
   double upper[], middle[], lower[], atrBuf[];
   ArraySetAsSeries(upper,  true);
   ArraySetAsSeries(middle, true);
   ArraySetAsSeries(lower,  true);
   ArraySetAsSeries(atrBuf, true);

   if(CopyBuffer(hBB, UPPER_BAND,  0, 3, upper)  < 3) return;
   if(CopyBuffer(hBB, BASE_LINE,   0, 3, middle) < 3) return;
   if(CopyBuffer(hBB, LOWER_BAND,  0, 3, lower)  < 3) return;
   if(CopyBuffer(hATR, 0,          0, 3, atrBuf) < 3) return;

   double atr = atrBuf[1];  // previous completed bar ATR

   //--- Squeeze detection: bandwidth = (upper - lower) / middle
   double bwPrev    = (upper[2] - lower[2]) / middle[2];
   double bwCurrent = (upper[1] - lower[1]) / middle[1];
   bool inSqueeze   = bwPrev < SqueezePct;
   bool expanding   = bwCurrent > bwPrev;

   //--- Price of last closed bar
   double closePrice[1];
   ArraySetAsSeries(closePrice, true);
   if(CopyClose(_Symbol, _Period, 1, 1, closePrice) < 1) return;
   double close1 = closePrice[0];

   //--- Current spread guard
   double spread = SymbolInfoInteger(_Symbol, SYMBOL_SPREAD) * _Point;
   if(spread > 3 * _Point * 10) return;  // skip wide spread

   double ask = SymbolInfoDouble(_Symbol, SYMBOL_ASK);
   double bid = SymbolInfoDouble(_Symbol, SYMBOL_BID);

   //--- Manage trailing stops on existing positions
   if(UseTrailingStop) ManageTrailingStop(atr);

   //--- Exit: close long if price crosses back below middle band
   for(int i = PositionsTotal() - 1; i >= 0; i--)
     {
      ulong ticket = PositionGetTicket(i);
      if(ticket == 0) continue;
      if(PositionGetString(POSITION_SYMBOL) != _Symbol) continue;
      if(PositionGetInteger(POSITION_MAGIC) != MagicNumber) continue;
      ENUM_POSITION_TYPE posType = (ENUM_POSITION_TYPE)PositionGetInteger(POSITION_TYPE);
      if(posType == POSITION_TYPE_BUY && close1 < middle[1])
         trade.PositionClose(ticket);
      else if(posType == POSITION_TYPE_SELL && close1 > middle[1])
         trade.PositionClose(ticket);
     }

   //--- Entry: only if no open trades and squeeze + expansion confirmed
   if(CountOpenPositions() >= MaxTrades) return;
   if(!inSqueeze || !expanding) return;

   //--- Long breakout: close above upper band
   if(close1 > upper[1])
     {
      double sl = NormalizeDouble(ask - ATR_SLMultiple * atr, _Digits);
      double tp = 0;  // exit via middle band cross
      MqlTradeRequest request = {};
      MqlTradeResult  result  = {};
      request.action    = TRADE_ACTION_DEAL;
      request.symbol    = _Symbol;
      request.volume    = LotSize;
      request.type      = ORDER_TYPE_BUY;
      request.price     = ask;
      request.sl        = sl;
      request.tp        = tp;
      request.magic     = MagicNumber;
      request.comment   = "BB_Squeeze_Long";
      request.deviation = 10;
      if(!OrderSend(request, result))
         Print("BUY OrderSend failed: ", result.retcode, " - ", result.comment);
      else
         Print("BUY opened at ", ask, " SL=", sl);
     }
   //--- Short breakout: close below lower band
   else if(close1 < lower[1])
     {
      double sl = NormalizeDouble(bid + ATR_SLMultiple * atr, _Digits);
      double tp = 0;
      MqlTradeRequest request = {};
      MqlTradeResult  result  = {};
      request.action    = TRADE_ACTION_DEAL;
      request.symbol    = _Symbol;
      request.volume    = LotSize;
      request.type      = ORDER_TYPE_SELL;
      request.price     = bid;
      request.sl        = sl;
      request.tp        = tp;
      request.magic     = MagicNumber;
      request.comment   = "BB_Squeeze_Short";
      request.deviation = 10;
      if(!OrderSend(request, result))
         Print("SELL OrderSend failed: ", result.retcode, " - ", result.comment);
      else
         Print("SELL opened at ", bid, " SL=", sl);
     }
  }
//+------------------------------------------------------------------+

Copy this code into MetaEditor, save it in the MQL5/Indicators folder, and compile with F7.

Change the settings or add your own signal filter

Describe the ATR inputs, alert rules, visual style, or confirmation filter you want. Pineify generates editable MQL5 source code that you can inspect and compile in MetaEditor.

Generate custom MQL5 code See the H1 version

Pine Script vs MQL5: Same Strategy, Different Platforms

Aspect	Pine Script (TradingView)	MQL5 (MetaTrader 5)
Execution	Series evaluated on chart updates	Event handlers with explicit buffers
Deployment	Runs in TradingView with alerts	Runs in the MT5 terminal or on a VPS
Broker access	Via TradingView broker integration	Direct broker connectivity
Backtesting	Strategy Tester for strategy scripts	Strategy Tester for Expert Advisors
Code complexity	Simpler, functional syntax	C++-like, more powerful

The calculation can be implemented on either platform, but the runtime model and buffer APIs differ. Read the Pine Script Supertrend reference before porting logic between them.

Frequently Asked Questions

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