XAUUSD Gold EA in MQL5 (2026) | ATR, Spread Filter, Session Rules

Build an EA for Gold (XAUUSD) in MQL5 — A Complete Case Study

You've built your first MA crossover EA and added risk management. Now it's time to apply that knowledge to a real-world case study: Gold (XAUUSD). Gold is one of the most traded commodities globally — it serves as a safe-haven asset, inflation hedge, and speculative instrument. Building an EA for gold requires symbol-specific adaptations that you won't find in generic forex tutorials. This article walks you through a complete, production-ready Gold EA with spread filters, session filters, and ATR-based stop loss — all based on official MQL5 documentation and best practices from trusted sources.

Why Gold as a Case Study

Gold is an ideal case study because it forces you to:

• Handle symbol-specific properties — Lot size, point value, and stops level differ from forex. You must use SymbolInfoDouble and SymbolInfoInteger instead of hardcoding values.
• Account for volatility — Gold can move $10–$30 within minutes on news. Fixed stop loss in points often fails; ATR-based stops adapt to current volatility.
• Filter by spread and session — Spreads widen during low liquidity or high volatility. The London–New York overlap (13:00–17:00 GMT) typically offers the best liquidity and tightest spreads.
• Validate your EA logic — A real case study teaches you to debug symbol-specific issues (e.g. "Not enough money", invalid stops) that generic EAs don't cover.

By the end of this article you will have a Gold EA that compiles, runs in the Strategy Tester on XAUUSD, and respects all symbol-specific requirements.

Gold-Specific Considerations

Key takeaway: Never hardcode lot size, point value, or stop distance. Always read them from the symbol at runtime:

double point   = SymbolInfoDouble(_Symbol, SYMBOL_POINT);
double volMin  = SymbolInfoDouble(_Symbol, SYMBOL_VOLUME_MIN);
double volStep = SymbolInfoDouble(_Symbol, SYMBOL_VOLUME_STEP);
long   stopsLevel = SymbolInfoInteger(_Symbol, SYMBOL_TRADE_STOPS_LEVEL);

Step 1: Strategy and Adaptations

We adapt the MA crossover strategy from our first EA with Gold-specific rules:

Session times: GMT is used. If your broker uses server time (e.g. GMT+2), adjust the hour range accordingly. Use TimeCurrent() and TimeToStruct() to check the current hour.

Step 2: Symbol Setup

Before coding, ensure XAUUSD is available:

1. Open MetaTrader 5 and go to View → Symbols (or press Ctrl+U).
2. In the Symbols window, expand Commodities or search for XAUUSD.
3. Right-click XAUUSD → Show in Market Watch.
4. Add XAUUSD to a chart (e.g. H1) — the EA will attach to this chart.

If XAUUSD is not listed, your broker may use a different name (e.g. GOLD, XAU/USD). Check your broker's symbol specification.

Step 3: Inputs and Handles

We need inputs for MA periods, risk, filters, and session:

#property copyright "AlfaTactix Academy"
#property version   "1.00"

input int    InpFastPeriod = 20;     // Fast MA period
input int    InpSlowPeriod = 50;     // Slow MA period
input double InpLotSize    = 0.01;   // Lot size (default 0.01 for gold)
input int    InpMagic      = 12346;  // Magic number
input int    InpMaxSpread  = 50;     // Max spread (points) to allow trade
input int    InpSessionStart = 13;   // Session start hour (GMT)
input int    InpSessionEnd   = 17;   // Session end hour (GMT)
input double InpAtrMultiplierSL = 2.0;  // ATR multiplier for Stop Loss
input double InpAtrMultiplierTP = 3.0;  // ATR multiplier for Take Profit

int g_fastHandle = INVALID_HANDLE;
int g_slowHandle = INVALID_HANDLE;
int g_atrHandle  = INVALID_HANDLE;

Note: We use 0.01 lot as default for gold — it is a common minimum. The EA will clamp to SYMBOL_VOLUME_MIN and SYMBOL_VOLUME_STEP in code.

Step 4: Spread and Session Filters

Before opening any trade, we check:

1. Spread filter:

long spread = SymbolInfoInteger(_Symbol, SYMBOL_SPREAD);
if(spread > InpMaxSpread) return;  // Skip trade — spread too wide

2. Session filter:

MqlDateTime dt;
TimeToStruct(TimeCurrent(), dt);
if(dt.hour < InpSessionStart || dt.hour >= InpSessionEnd) return;

Step 5: ATR-Based Stop Loss

Gold's volatility requires dynamic stops. We use iATR to get the Average True Range:

g_atrHandle = iATR(_Symbol, PERIOD_CURRENT, 14);

if(g_atrHandle == INVALID_HANDLE || CopyBuffer(g_atrHandle, 0, 0, 1, atrBuf) < 1)
   return;  // No ATR data — skip

double atr = atrBuf[0];
double slDist = atr * InpAtrMultiplierSL;
double tpDist = atr * InpAtrMultiplierTP;

// For Buy: SL below entry, TP above
double sl = SymbolInfoDouble(_Symbol, SYMBOL_ASK) - slDist;
double tp = SymbolInfoDouble(_Symbol, SYMBOL_ASK) + tpDist;

// Normalize and respect SYMBOL_TRADE_STOPS_LEVEL
int digits = (int)SymbolInfoInteger(_Symbol, SYMBOL_DIGITS);
double point = SymbolInfoDouble(_Symbol, SYMBOL_POINT);
long stopsLevel = SymbolInfoInteger(_Symbol, SYMBOL_TRADE_STOPS_LEVEL);
double minDist = stopsLevel * point;

if(slDist < minDist) slDist = minDist;  // Ensure SL is far enough
sl = NormalizeDouble(price - slDist, digits);
tp = NormalizeDouble(price + tpDist, digits);

Step 6: OnInit and OnTick

OnInit: Create handles for iMA (fast, slow) and iATR. Validate inputs and symbol:

int OnInit()
{
   if(InpFastPeriod <= 0 || InpSlowPeriod <= 0 || InpFastPeriod >= InpSlowPeriod)
   {
      Print("Invalid MA periods.");
      return(INIT_PARAMETERS_INCORRECT);
   }
   if(!SymbolSelect(_Symbol, true))
   {
      Print("Symbol ", _Symbol, " not found. Add to Market Watch.");
      return(INIT_FAILED);
   }

   g_fastHandle = iMA(_Symbol, PERIOD_CURRENT, InpFastPeriod, 0, MODE_EMA, PRICE_CLOSE);
   g_slowHandle = iMA(_Symbol, PERIOD_CURRENT, InpSlowPeriod, 0, MODE_EMA, PRICE_CLOSE);
   g_atrHandle  = iATR(_Symbol, PERIOD_CURRENT, 14);

   if(g_fastHandle == INVALID_HANDLE || g_slowHandle == INVALID_HANDLE || g_atrHandle == INVALID_HANDLE)
   {
      Print("Failed to create indicator handles. Error: ", GetLastError());
      return(INIT_FAILED);
   }
   return(INIT_SUCCEEDED);
}

OnTick: New-bar check → spread filter → session filter → crossover logic → open trade with ATR-based SL/TP. Reuse the logic from Build Your First EA for crossover detection and position management.

Step 7: Compile and Backtest

1. Compile in MetaEditor (F7).
2. Open Strategy Tester (Ctrl+R).
3. Select GoldEA (or your EA name).
4. Symbol: XAUUSD.
5. Timeframe: H1 (recommended for gold trend strategies).
6. Date range: At least 12 months for meaningful backtest.
7. Modeling: "Every tick" or "1 minute OHLC" for accuracy.
8. Run and check Results, Graph, and Journal tabs.

Summary — What You Built

Full Code

Here is the complete Gold EA. Save as GoldEA.mq5 in MQL5\Experts.

//+------------------------------------------------------------------+
//|                                                    GoldEA.mq5    |
//|                                    Gold (XAUUSD) Case Study EA   |
//+------------------------------------------------------------------+
#property copyright "AlfaTactix Academy"
#property version   "1.00"

input int    InpFastPeriod = 20;
input int    InpSlowPeriod = 50;
input double InpLotSize    = 0.01;
input int    InpMagic      = 12346;
input int    InpMaxSpread  = 50;
input int    InpSessionStart = 13;
input int    InpSessionEnd   = 17;
input double InpAtrMultiplierSL = 2.0;
input double InpAtrMultiplierTP = 3.0;

int g_fastHandle = INVALID_HANDLE;
int g_slowHandle = INVALID_HANDLE;
int g_atrHandle  = INVALID_HANDLE;

int OnInit()
{
   if(InpFastPeriod <= 0 || InpSlowPeriod <= 0 || InpFastPeriod >= InpSlowPeriod)
   {
      Print("Invalid MA periods.");
      return(INIT_PARAMETERS_INCORRECT);
   }
   if(!SymbolSelect(_Symbol, true))
   {
      Print("Symbol ", _Symbol, " not found.");
      return(INIT_FAILED);
   }
   g_fastHandle = iMA(_Symbol, PERIOD_CURRENT, InpFastPeriod, 0, MODE_EMA, PRICE_CLOSE);
   g_slowHandle = iMA(_Symbol, PERIOD_CURRENT, InpSlowPeriod, 0, MODE_EMA, PRICE_CLOSE);
   g_atrHandle  = iATR(_Symbol, PERIOD_CURRENT, 14);
   if(g_fastHandle == INVALID_HANDLE || g_slowHandle == INVALID_HANDLE || g_atrHandle == INVALID_HANDLE)
   {
      Print("Failed to create handles. Error: ", GetLastError());
      return(INIT_FAILED);
   }
   return(INIT_SUCCEEDED);
}

void OnDeinit(const int reason)
{
   if(g_fastHandle != INVALID_HANDLE) IndicatorRelease(g_fastHandle);
   if(g_slowHandle != INVALID_HANDLE) IndicatorRelease(g_slowHandle);
   if(g_atrHandle  != INVALID_HANDLE) IndicatorRelease(g_atrHandle);
}

void OnTick()
{
   static datetime lastBar = 0;
   datetime currentBar = iTime(_Symbol, PERIOD_CURRENT, 0);
   if(currentBar == lastBar) return;
   lastBar = currentBar;

   if(SymbolInfoInteger(_Symbol, SYMBOL_SPREAD) > InpMaxSpread) return;  // Spread filter

   MqlDateTime dt;
   TimeToStruct(TimeCurrent(), dt);
   if(dt.hour < InpSessionStart || dt.hour >= InpSessionEnd) return;  // Session filter

   double fast[], slow[], atrBuf[];
   ArraySetAsSeries(fast, true);
   ArraySetAsSeries(slow, true);
   ArraySetAsSeries(atrBuf, true);
   if(CopyBuffer(g_fastHandle, 0, 0, 3, fast) < 3) return;
   if(CopyBuffer(g_slowHandle, 0, 0, 3, slow) < 3) return;
   if(CopyBuffer(g_atrHandle, 0, 0, 1, atrBuf) < 1) return;

   bool buySignal  = (fast[1] > slow[1]) && (fast[2] <= slow[2]);
   bool sellSignal = (fast[1] < slow[1]) && (fast[2] >= slow[2]);

   double atr = atrBuf[0];
   int digits = (int)SymbolInfoInteger(_Symbol, SYMBOL_DIGITS);
   double point = SymbolInfoDouble(_Symbol, SYMBOL_POINT);
   long stopsLevel = SymbolInfoInteger(_Symbol, SYMBOL_TRADE_STOPS_LEVEL);
   double minDist = MathMax(stopsLevel * point, point);

   double volMin = SymbolInfoDouble(_Symbol, SYMBOL_VOLUME_MIN);
   double volMax = SymbolInfoDouble(_Symbol, SYMBOL_VOLUME_MAX);
   double volStep = SymbolInfoDouble(_Symbol, SYMBOL_VOLUME_STEP);
   double lot = MathMax(volMin, MathMin(volMax, InpLotSize));
   lot = MathFloor(lot / volStep) * volStep;
   lot = NormalizeDouble(lot, 2);

   if(buySignal)
   {
      ClosePositions(POSITION_TYPE_SELL);
      if(CountPositions(POSITION_TYPE_BUY) == 0)
      {
         double ask = SymbolInfoDouble(_Symbol, SYMBOL_ASK);
         double slDist = MathMax(atr * InpAtrMultiplierSL, minDist);
         double tpDist = MathMax(atr * InpAtrMultiplierTP, minDist);
         double sl = NormalizeDouble(ask - slDist, digits);
         double tp = NormalizeDouble(ask + tpDist, digits);
         OpenBuy(lot, sl, tp);
      }
   }
   else if(sellSignal)
   {
      ClosePositions(POSITION_TYPE_BUY);
      if(CountPositions(POSITION_TYPE_SELL) == 0)
      {
         double bid = SymbolInfoDouble(_Symbol, SYMBOL_BID);
         double slDist = MathMax(atr * InpAtrMultiplierSL, minDist);
         double tpDist = MathMax(atr * InpAtrMultiplierTP, minDist);
         double sl = NormalizeDouble(bid + slDist, digits);
         double tp = NormalizeDouble(bid - tpDist, digits);
         OpenSell(lot, sl, tp);
      }
   }
}

void OpenBuy(double lot, double sl, double tp)
{
   MqlTradeRequest req = {};
   MqlTradeResult  res = {};
   req.action   = TRADE_ACTION_DEAL;
   req.symbol   = _Symbol;
   req.volume   = lot;
   req.type     = ORDER_TYPE_BUY;
   req.price    = SymbolInfoDouble(_Symbol, SYMBOL_ASK);
   req.sl       = sl;
   req.tp       = tp;
   req.deviation = 20;
   req.magic    = InpMagic;
   if(!OrderSend(req, res)) Print("OpenBuy failed: ", GetLastError());
}

void OpenSell(double lot, double sl, double tp)
{
   MqlTradeRequest req = {};
   MqlTradeResult  res = {};
   req.action   = TRADE_ACTION_DEAL;
   req.symbol   = _Symbol;
   req.volume   = lot;
   req.type     = ORDER_TYPE_SELL;
   req.price    = SymbolInfoDouble(_Symbol, SYMBOL_BID);
   req.sl       = sl;
   req.tp       = tp;
   req.deviation = 20;
   req.magic    = InpMagic;
   if(!OrderSend(req, res)) Print("OpenSell failed: ", GetLastError());
}

int CountPositions(ENUM_POSITION_TYPE type)
{
   int count = 0;
   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) != InpMagic) continue;
      if(PositionGetInteger(POSITION_TYPE) != type) continue;
      count++;
   }
   return count;
}

void ClosePositions(ENUM_POSITION_TYPE type)
{
   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) != InpMagic) continue;
      if(PositionGetInteger(POSITION_TYPE) != type) continue;

      MqlTradeRequest req = {};
      MqlTradeResult  res = {};
      req.action   = TRADE_ACTION_DEAL;
      req.position = ticket;
      req.symbol   = _Symbol;
      req.volume   = PositionGetDouble(POSITION_VOLUME);
      req.deviation = 20;
      req.magic    = InpMagic;
      req.type     = (type == POSITION_TYPE_BUY) ? ORDER_TYPE_SELL : ORDER_TYPE_BUY;
      req.price    = (type == POSITION_TYPE_BUY) ? SymbolInfoDouble(_Symbol, SYMBOL_BID) : SymbolInfoDouble(_Symbol, SYMBOL_ASK);
      OrderSend(req, res);
   }
}

Troubleshooting

Next Steps

Extend this EA with multi-timeframe filters and trailing stops. Before going live, deploy to Demo first and backtest thoroughly.

Bonus Tip: Want to design this Gold EA visually? Try AlfaTactix Strategy Builder free — add MA crossover, ATR-based SL, spread and session filters with a visual interface, then export MQL5 for XAUUSD. Same logic, zero typing.