Do Sunday-open gaps fill during the Asian session? A way to check

[FXS London Scalper]

Weekend gaps on EURUSD, GBPUSD and AUDUSD get a lot of folklore. Checking whether they fill is straightforward with H1 data.

Method:

• List every Sunday open with a gap above 10 pips from Friday's close.
• Record whether price touched Friday's close before 08:00 London on Monday, later in the week, or not at all by Friday.
• Note whether anything happened over the weekend: a vote, remarks from a policymaker, a geopolitical shock.

Two things to keep in mind before trading it:

Spreads. The Sunday open has very wide spreads, often several pips in the first 15 minutes. Part of the gap you see on a bid chart isn't a tradable price. Check the ask too.

Selection. Gaps caused by real weekend news are exactly the ones least likely to fill, and exactly the ones where fading is most dangerous. Split your results by news and no-news gaps, or the average will mislead you.

A modest way to use it without trading the gap: if the gap is still open at 08:00 London on Monday, treat Friday's close as a level for the morning. That uses the information without taking the Sunday spread risk.

Has anyone tracked this over several years?

[Amanhasnoname]

I tracked this on EURUSD and AUDUSD for about three years in a plain spreadsheet, and the news split you mention was the whole story. Gaps with no obvious weekend cause filled before London on Monday more often than not, somewhere around two thirds of the time in my sample. Gaps that followed a real event, like a central bank official speaking on Saturday or a surprise result somewhere, filled before London in fewer than a third of cases, and a fair number never filled that week at all.

The spread point is bigger than people expect. When I compared the bid chart with the ask on my broker, a 14 pip gap on AUDUSD was really closer to 9 tradable pips for the first twenty minutes, because the ask was miles away from the bid.

So I never fade the Sunday open itself any more. I do exactly what you describe and keep Friday's close on the chart as a morning level. It has given me some clean reactions around 08:00 London that I'd otherwise have missed.