S&P 500 Opening-Range Breakouts: New York Holds, London Snaps Back
Share of breakout sessions (%)
We found earlier that gold's opening-range breakout is a trap in London and structurally cleaner in New York. That raised an obvious question: is that a gold-specific quirk, or a session-quality effect that shows up across instruments? We ran the same test on the S&P 500's first 60 minutes.
Two sessions, two very different failure modes
Tracking every H1 close beyond the opening range through to session end:
London (07:00 UTC open) — 131 breakout sessions
| Outcome | Count | Share |
|---|---|---|
| Clean success (extends 1× the opening range) | 25 | 19.1% |
| Fakeout (closes back inside) | 36 | 27.5% |
| Roundtrip (Judas — opposite side breaks too) | 70 | 53.4% |
New York (13:00 UTC open) — 130 breakout sessions
| Outcome | Count | Share |
|---|---|---|
| Clean success (extends 1× the opening range) | 27 | 20.8% |
| Fakeout (closes back inside) | 70 | 53.8% |
| Roundtrip (Judas — opposite side breaks too) | 21 | 16.2% |
| No clean resolution | 12 | 9.2% |
The clean-success rate is nearly identical between sessions — roughly one in five opening-range breaks actually extends and holds, in London or New York. What's completely different is what happens to the other 80%. In New York, most of those failures just fizzle (fakeout, close back inside). In London, more than half of all sessions see both sides of the opening range broken before the day is done — a genuine Judas swing, not just a failed break.
Why this matters more than the headline number
A trader who takes the first London breakout at face value is walking into the highest-roundtrip session we've measured on this instrument — worse, proportionally, than gold's own London ORB trap. A trader doing the identical thing in New York is over three times less likely to get faked out in both directions.
The opening ranges themselves are structurally different too: London's is tighter relative to volatility (median ~0.41× H4 ATR) than New York's (median ~0.90× H4 ATR), which is part of why London's breaks are cheaper to fake — a narrower range takes less adverse movement to invalidate and reverse.
What this means
The exact stop and target placement we trade stay private, but the pattern is consistent across two unrelated instruments now:
- "First breakout of the session" is not a session-neutral setup. The same mechanical rule produces a coin-flip-plus in one session and a trap in another, on gold and on the S&P alike.
- London's opening range is the one to treat with the most suspicion. Over half the time, both sides break before the session settles — plan for the sweep, not just the first move.
- New York's opening range is comparatively trustworthy. Fakeouts still happen more than half the time, but true double-direction whipsaws are rare.
If a breakout system works session-agnostically on paper, this is the kind of asymmetry that will quietly eat the backtest's edge in live London trading.
Studies like this become the filters inside a documented playbook — the research → playbook → backtest → live loop, locked to one instrument at a time, rather than a scanner firing on everything.