Mean Reversion Intraday: When Ranges Dominate

What you will learn

• What mean reversion means on an intraday chart.
• Which conditions suggest a range day rather than a trend day.
• How VWAP standard-deviation bands are calculated and used for entries and targets.
• How to judge a mean-reversion setup with its break-even win rate and clear exit rules.

Explanation

Mean reversion is the tendency of price to move back towards an average after a stretch away from it. Range trading on higher timeframes was covered in the course "Trading". Intraday, the "average" is usually VWAP, and the trade idea is a fade: selling a stretch up, or buying a stretch down, and targeting a return to VWAP.

Mean reversion is the opposite of momentum trading. The two setups need opposite market conditions, so the first task every day is to decide which condition you are in.

Range-day conditions

• The open and the opening range are inside the prior day's range (no large gap).
• VWAP is flat, and price has crossed it several times.
• RVOL is around 1 or lower: no special news or interest.
• Breakouts of the opening range have failed and returned inside.

If price makes a strong move with high RVOL and VWAP starts to slope, the day may be changing into a trend day. Fading a trend day is one of the most expensive intraday errors.

VWAP standard-deviation bands

Bands show how far price is from VWAP compared with today's normal spread of prices. The volume-weighted standard deviation σ (sigma) is:

σ = √( Σ volume × (typical price − VWAP)² ÷ Σ volume )

Upper band = VWAP + k × σ; lower band = VWAP − k × σ. Common choices are k = 1 and k = 2. Most charting platforms calculate the bands automatically; you need the formula to understand what they show, not to calculate them by hand.

A fade plan

1. Location: price reaches the 2σ band, or the edge of the day's range.
2. Trigger: a rejection on the execution chart, for example a 5-minute bar that closes back inside the band.
3. Stop: beyond the extreme of the stretch, plus a buffer.
4. Target: VWAP. The reward-to-risk ratio is often modest, around 1 to 1.5.
5. Abort rule: exit early if two 5-minute bars close outside the band and VWAP begins to slope towards the move.

Why costs matter more here

Because targets are small, costs take a large share of the reward. Use the break-even win rate from Lesson 1: (1 + c) ÷ (RR + 1), where c is cost in R. A mean-reversion setup needs a higher win rate than a momentum setup; check whether your records support it.

Worked example

Hypothetical example: a hypothetical "Index X" CFD worth €1 per point, spread 1.0 point. The prior day's range was 9,900–10,100. Today the opening range is inside it, RVOL is 0.9 and VWAP is flat at 10,030. The upper 2σ band is at 10,060. Risk budget €100. Financing costs and taxes are excluded.

1. Price rises to 10,062, then a 5-minute bar closes back inside the band at 10,055. Plan: sell at 10,055.
2. Stop: 10,075, above the high of 10,062 with a buffer. Risk: 10,075 − 10,055 = 20 points.
3. Size: €100 ÷ 20 points = 5 units (€5 per point).
4. Target: VWAP at 10,030. Reward: 10,055 − 10,030 = 25 points. RR = 25 ÷ 20 = 1.25.
5. Cost: 1.0 point × 5 units = €5 = 0.05R.
6. Net win: 25 × €5 − €5 = €120 = 1.20R. Net loss: 20 × €5 + €5 = €105 = 1.05R.
7. Break-even win rate without costs: 1 ÷ (1.25 + 1) = 44.4%. With costs: (1 + 0.05) ÷ 2.25 = 46.7%.

The trader must win more than about 47 out of 100 such trades to break even. If the day turns into a trend day, the abort rule should end the trade before the full stop is hit, but a fast move can also fill the stop worse than 10,075.

Common mistake

Practice activity

On paper: on a range day, Index X (€1 per point, spread 1.2 points) falls to the lower band and a 5-minute bar closes back inside at 9,948. Your stop is at 9,930 and VWAP is at 9,975. Risk budget €90. Calculate (a) size, (b) RR, (c) cost in R, (d) break-even win rate with costs, (e) net euro result of a win and of a loss.

Key takeaways

• Mean reversion targets a return to VWAP and works best on range days.
• Check range-day conditions first: open inside yesterday's range, flat VWAP, low RVOL, failed breakouts.
• Bands = VWAP ± k × σ; use a rejection trigger, a stop beyond the extreme and an abort rule.
• Small targets make costs heavy; calculate the break-even win rate after costs.

Next step

In the next lesson, you will look closely at execution during the day: order types, spreads and slippage, and how they change your results.