ES Futures Gap Fill Strategy: How to Trade Opening Gaps

Gap fill trades tempt because the target is obvious: yesterday's close sits right there on the chart. The problem is that once you add a realistic stop, the trade often pays about what it risks, so the number that matters is how often the gap fills in your data, and you should not take that from anyone's headline statistic.

Define the gap before you trade it

ES trades on Globex nearly around the clock, so there is no single obvious gap. The usual definition compares the prior regular session close (4:00 PM ET) with the regular session opening print (9:30 AM ET). Your charting platform may draw it differently depending on the session template, so check which prices you are measuring. Write the definition into your rules, and use the same one when you collect data.

The gap is the result of overnight trading in thinner liquidity: global news, data releases at 8:30 AM ET, central bank decisions and earnings from large companies after the close. When a catalyst is large and still developing, the move can extend instead of reverting.

Do not rely on a quoted fill rate

You will see claims that a large percentage of gaps fill. I am not going to repeat one, because the answer depends on the dates, the definition of a gap, the size bucket and whether you count a fill at any time that day or a fill you could have traded. Measure it yourself on the product you trade:

1. Pick a data source and a clear gap definition.
2. Record the gap size, direction, day of week, whether a scheduled event hit, and whether price touched the prior close that day.
3. Group by size and compare the fill frequency, plus how far price moved against you before it filled.
4. Look at the adverse excursion. A gap that fills after a 12-point move against your stop is not a trade you got paid on.

Small samples mislead. Thirty trades is not a statistically proven edge, and fifty simulated trades is not live proof.

A worked hypothetical

Prior close 5,000.00. The open prints at 5,010.00, a 10-point gap up. The first five minutes form an opening range with a high of 5,012.00 and a low of 5,007.00. You plan to short a break below the range low, aiming at the prior close.

• Entry: 5,006.75 (one tick below the range low).
• Stop: 5,013.50 (six ticks above the range high).
• Risk: 6.75 points, which is $337.50 on one ES or $33.75 on one MES.
• Target: 5,000.00, a reward of 6.75 points.

That is about 1:1. Most of the gap was already gone by the time the setup triggered. A breakeven win rate at 1:1 is above 50% once you add commissions and slippage. That is why waiting for the opening range does not automatically improve the trade, and why you should calculate the numbers each time instead of assuming a 2:1. Scaling out halfway, at about 5,003.38, reduces the reward on the runner and changes the math again, so model the whole plan.

When the setup does not apply

Stand aside, or at least question the trade, when any of these is true:

• A scheduled release or decision is still coming, such as an FOMC day.
• The gap came from a large surprise and price is still moving away from the prior close.
• The gap is very large compared with the average daily range you see.
• The opening range is so wide that the stop makes the trade worse than 1:1.

If the range breaks against you, your stop defines the loss. Do not widen it. Gaps that fail to show fill pressure early can turn into trend days, and one oversized loss can undo many small wins.

Using levels from the open

KPL levels are fixed reference prices anchored to the regular-session opening print, so they do not exist until 9:30 ET. After the open prints, you can compare the gap-fill target with those levels as additional context for stops and targets. That is context for planning, not evidence that a trade has a higher chance of working. KPL does not predict prices, and the gap trade and the levels are separate tools. You can read about the method on the KPL strategy page.

Common mistakes

1. Entering at the opening bell, when the first minutes are the least reliable for fills.
2. Not computing reward-to-risk with the actual stop distance and costs.
3. Treating all gap sizes the same, when small gaps leave no room after costs.
4. Ignoring the calendar.
5. Moving the stop.

Journal each trade with the gap size, catalyst, range width, entry, stop, target and result, and review the whole set before changing a rule. For time-of-day context, see best time to trade ES futures, and for the course and daily levels there is the 7-day trial.