How to Code Stop Loss and Take Profit in Pine Script

Stop Loss and Take Profit approaches in Pine Script: Points vs. Price levels

When writing risk management rules in Pine Script, developers choose between two syntax models in strategy.exit(): relative offsets (loss and profit) or absolute price levels (stop and limit). Using absolute price levels is generally preferred for advanced strategies because it accommodates technical chart levels, swing highs/lows, and ATR bands directly.

Complete Pine Script v6 ATR stop loss and break-even strategy code

The following complete Pine Script v6 strategy demonstrates how to enter on a Donchian breakout, set an initial ATR stop loss, target a 2:1 profit ratio, and automatically ratchet the stop loss to break-even once price achieves 1R in profit.

//@version=6
strategy("ATR Stop Loss & Break-Even [v6]", overlay = true, initial_capital = 10000, default_qty_type = strategy.percent_of_equity, default_qty_value = 10)

// Inputs
lengthChannel = input.int(20, "Donchian Length")
atrLength = input.int(14, "ATR Length")
atrMultiplier = input.float(1.5, "ATR Stop Multiplier")
riskRewardRatio = input.float(2.0, "Risk:Reward Ratio")
enableBreakEven = input.bool(true, "Enable Break-Even Stop")

// Calculations
highestHigh = ta.highest(high, lengthChannel)[1]
lowestLow = ta.lowest(low, lengthChannel)[1]
atrVal = ta.atr(atrLength)

plot(highestHigh, "Channel High", color = color.green)
plot(lowestLow, "Channel Low", color = color.red)

// Entry trigger
longCondition = ta.crossover(close, highestHigh)

if longCondition and strategy.position_size == 0
    strategy.entry("Long", strategy.long)

// Dynamic exit calculation
if strategy.position_size > 0
    entryPrice = strategy.position_avg_price
    riskDistance = atrVal * atrMultiplier
    initialStop = entryPrice - riskDistance
    targetPrice = entryPrice + (riskDistance * riskRewardRatio)
    
    // Check if price reached 1R profit for break-even trigger
    beTriggerPrice = entryPrice + riskDistance
    isBreakEvenActive = enableBreakEven and (high >= beTriggerPrice)
    
    // Select active stop level
    activeStop = isBreakEvenActive ? math.max(initialStop, entryPrice) : initialStop
    
    strategy.exit("Exit Long", from_entry = "Long", stop = activeStop, limit = targetPrice)

Coding ATR-based dynamic stop loss

Using ta.atr() to size stops prevents getting stopped out by routine noise while maintaining tight defense when markets tighten. Key considerations when coding ATR stops include:

• Anchor to entry bar ATR: Store the ATR value at the exact time of order fill using var or strategy.position_avg_price offsets so your stop loss does not expand retroactively as volatility increases during an open trade.
• Symmetric risk for short positions: For short entries, add the ATR multiplier to the entry price: entryPrice + (atr * mult).
• Account for spread and slippage: Always leave a minimum buffer beyond recent swing extremes so normal bid-ask spread does not trigger accidental stops.

How to move stop loss to break-even safely

Moving a stop loss to break-even creates a "free trade" scenario, but doing so too early cuts off profitable moves prematurely. Follow these guidelines when coding break-even logic:

• Wait for minimum 1R extension: Moving to break-even before price has moved at least 1x your initial risk frequently results in chop exits before the trend establishes.
• Add a tick buffer above entry: True break-even should cover execution commission and exchange fees. Set stop = entryPrice + (syminfo.mintick * 5) for longs.
• Never move stops in reverse: Ensure your stop updating logic uses math.max() for long trades so an updated stop can only move in favor of your position, never backward.