Double Bollinger Bands add a second, narrower pair of bands to the classic indicator. The idea is simple: when price closes in the outer zone, a trend is under way; when it falls back into the middle, the trend has paused. Below are the rules, a real trade on AUD/USD, and the results of testing the plain version on five currency futures from 2014 to 2026. The results are not what most strategy pages suggest.
The setup
| Line or zone | Setting | Meaning |
|---|---|---|
| Middle line | 20-period simple moving average | The average price |
| Inner bands | ±1 standard deviation | The edge of normal movement |
| Outer bands | ±2 standard deviations | The classic Bollinger Bands |
| Buy zone | Between +1 and +2 standard deviations | Closes here suggest an uptrend |
| Sell zone | Between −1 and −2 standard deviations | Closes here suggest a downtrend |
| Neutral zone | Between the two inner bands | No clear trend |
The approach was popularised among forex traders by Kathy Lien. If you are new to the indicator, start with our guide to the Bollinger Band squeeze, which explains how the bands are calculated.
The basic rules
- Wait for a quiet period: closes inside the neutral zone for at least ten days.
- Buy when a candle closes in the buy zone (above the +1 band); sell when it closes in the sell zone.
- Put the stop at the 20-period average.
- Exit when a candle closes back inside the neutral zone.
Real example: AUD/USD, September 2024
The chart at the top of this article shows the trade. After a quiet first half of September 2024, the Australian dollar closed at 0.6791 on 18 September, just above the +1 band at 0.6784: an entry in the buy zone, with the stop at the average, 0.6737, 54 pips away.
- Price stayed in the buy zone for two weeks and reached 0.6941 on 30 September.
- On 3 October it closed at 0.6841, back below the +1 band, which triggered the exit.
- Result: about +50 pips, close to one times the risk, but roughly 100 pips below the high. The exit rule gives back part of every move.
What a 12-year test showed
We applied exactly the rules above to daily data for the euro, pound, Australian dollar, yen and Swiss franc futures from 2014 to 2026, without spreads or commissions. Results are measured in R, the distance between entry and stop.
- 120 trades, of which only 18% were winners.
- The average trade lost 0.35R, and the average trade lasted just 3.4 days.
- The few big trends carried everything: the best 10% of trades produced about 91% of all gains. The best was a +2.7R short in the euro in February 2015.
- With trading costs included, the results would be worse, not better.
In other words, the plain version is not a profitable system on its own. Most entries happen just as a short burst ends, and price falls back into the neutral zone within days. What the bands do well is describe the state of the market: whether a trend is in progress or not.
A better way to use double Bollinger Bands
- As a trend filter: only look for buy setups, such as a price action signal or a pullback, while closes stay in the buy zone, and the opposite in the sell zone.
- As a reason to stay out: when closes are in the neutral zone, trend strategies tend to fail; range methods such as our RSI range strategy fit better.
- Together with a volatility signal: a breakout from a TTM squeeze that also closes in the buy or sell zone is a stronger start than either signal alone.
- With a higher-timeframe filter such as the 200 EMA, so you only trade in the direction of the larger trend.
Common mistakes
- Treating every close above the +1 band as a buy signal, which is exactly the rule that lost in our test.
- Moving the exit further away after the fact to keep winning trades in the chart.
- Ignoring position size: with stops at the average, the distance changes every day; use our position size calculator and keep risk at 1–2%.
Frequently asked questions
What settings should I use?
The usual settings are a 20-period average with bands at 1 and 2 standard deviations. Some traders use 2 and 3 for the outer pair; the logic of the zones is the same.
Which timeframe works best?
The daily and 4-hour charts give the clearest zones. On very short timeframes price crosses the inner bands constantly and costs grow.
Is the double Bollinger Bands strategy profitable?
Not in its plain mechanical form, according to our test. It is useful for reading whether a market is trending, and as part of a plan with a separate entry signal and strict risk management.
For the original definition of the bands, see the John Bollinger’s official site. Forex and CFD trading on margin is high-risk and most retail traders lose money. Past results do not guarantee future results, and nothing here is financial advice.