Triple witching: $6.2 trillion hangs over the S&P 500
Published on September 18, 2026
Triple witching lands at an awkward moment for the S&P 500. Around $6.2 trillion of US options expire today, two days after the Fed raised rates and hours after the Bank of Japan did the same. The index walks into that expiry off a strong bounce, with almost nothing holding it up below 7,600.
Why triple witching bends the indexes
Three contract types expire together today. Stock options, stock index options and stock index futures. EBC Financial Group cites a Citadel Securities estimate that puts the expiry near $6.2 trillion, roughly a quarter of all US options exposure.
That number is not decoration. When this many positions unwind on one day, dealer hedging sets the price, not earnings. Settlement also spreads across the session. Standard index options settle off the opening prints, weekly contracts settle at the close. Index futures already rolled to the next contract on September 14, the CME roll date.
For a futures trader that means two things. Volume swells, and moves can run fast with no fundamental story behind them.
The Fed and the Bank of Japan loaded the week
On Wednesday the Fed raised its policy rate by 25 basis points to a 3.75% to 4% range. It was the first hike since July 2023 and the vote was unanimous. Chair Kevin Warsh did not soften it. "The plain fact is that inflation is too high and has been for too long," he said. TheStreet reports that 16 of the 18 officials still pencil in at least one more hike this year.
Stocks sold off first, then took it all back. On Thursday the S&P 500 gained 1.14% to 7,638.16, the Nasdaq Composite 1.67% to 26,413 and the Dow 0.71% to 51,827, according to Yahoo Finance. The 10-year Treasury yield eased to 4.94% and WTI crude dropped below $101, which helped.
Matthew Miskin of Manulife John Hancock caught the mood. The decision "does make them look independent, it adds trust to the market," he said, while adding that the Fed "may have come off a little too hawkish in this meeting." James DePorre of TheStreet Pro points at the real driver. "The inflation driving this whole stretch is coming from oil and the Iran war."
Early today the Bank of Japan followed. A 25 basis point hike to 1.25% on a seven to two vote, the highest policy rate since 1993. The yen got no reward for it and the dollar climbed back toward 156, the usual sell the fact reaction. Goldman Sachs now sees a growing case for a quicker pace, with room for another move as soon as December.
The 7,600 gamma wall on the S&P 500
This is where the mechanics get concrete. Mott Capital Management places the bulk of S&P 500 options gamma at 7,600, a put wall at 7,500 and a call wall at 8,000. The flip point sits near 7,672, with net gamma around minus $14.8 billion.
In plain terms. Above 7,672 dealers sell rallies and buy dips, which cools the tape. Below it they do the opposite and push moves further. The S&P 500 closed Thursday at 7,638, right between the two. The VIX is still low at 15.44 while CNN's Fear and Greed Index reads 29, in fear territory. Quiet on the surface, tight underneath.
Key levels today
| Instrument | Level (support / resistance) | Change (September 17 session) | Scenario to watch |
|---|---|---|---|
| S&P 500 | Support 7,600, flip 7,672, resistance 8,000 | +1.14% | Above 7,672 hedging caps the swings. Below 7,600 the next real floor is 7,500 |
| USD/JPY | Support 153, resistance 160 | -0.52% | The dollar rebounded toward 156 after the BOJ. Under 153 the market starts pricing Japanese tightening seriously |
Economic calendar
9:15am ET, US industrial production, consensus +0.3%. A stronger print hands the argument back to the hawks and sends the 10-year yield toward 5% again.
10:00am ET, Conference Board leading index, consensus +0.1%. A negative reading puts the slowdown story back in play and hits cyclicals first.
4:00pm ET, final settlement of the expiry. If the S&P 500 finishes glued to 7,600 or 7,650, that is strike pinning, not a trend signal.
Next Wednesday, 9:45am ET, US flash PMIs. Services above 50 keeps the soft landing case alive. Below 50 and the slowdown question returns fast.
The bottom line
The S&P 500 meets the largest options expiry of the quarter straight after two rate hikes, with 7,600 as its only genuine support. While the VIX stays under 20 the day's risk is mechanical before it is macro, and the daily index tracker lives on our market page.
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This is not investment advice. Informational content only.