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0DTE on monthly OPEX days: SPX, SPY and QQQ

CalendarMonthly OPEXverified 2026-09-26

AM-settled SPX monthlies settle on the opening print; PM-settled SPXW and the ETF options settle on the close. The archive's 0DTE slice is the PM-settled contracts — see what happens when SPX expires in the money.

Next Monthly OPEX date in the calendar file: — Monthly OPEX (third Friday; AM-settled SPX + PM-settled SPXW, ETF options) (Cboe 2026 options calendar, verified 2026-09-26).

Simulator SPX

your strike at the close

Every Monthly OPEX date in the calendar file, with its primary source
DateDayEventWhat the archive will showSource
2026-10-16FridayMonthly OPEX Monthly OPEX (third Friday; AM-settled SPX + PM-settled SPXW, ETF options)SPX/SPY/QQQ session pages after the close on 2026-10-16Cboe 2026 options calendar (cdn.cboe.com)
verified 2026-09-26
2026-11-20FridayMonthly OPEX Monthly OPEX (third Friday; AM-settled SPX + PM-settled SPXW, ETF options)SPX/SPY/QQQ session pages after the close on 2026-11-20Cboe 2026 options calendar (cdn.cboe.com)
verified 2026-09-26
2026-12-18FridayMonthly OPEX Monthly OPEX (third Friday; AM-settled SPX + PM-settled SPXW, ETF options)SPX/SPY/QQQ session pages after the close on 2026-12-18Cboe 2026 options calendar (cdn.cboe.com)
verified 2026-09-26

Across monthly OPEX days

n = 0 archived monthly OPEX days: no statistics until 5 archived instances — the per-session numbers are below as each date passes.

Quick answers

Is monthly OPEX different from a normal 0DTE day?

AM-settled SPX monthlies settle on the opening print; PM-settled SPXW and the ETF options settle on the close. The archive's 0DTE slice is the PM-settled contracts — see what happens when SPX expires in the money.

When is the next Monthly OPEX day?

2026-10-16 (Friday): Monthly OPEX (third Friday; AM-settled SPX + PM-settled SPXW, ETF options), per the Cboe 2026 options calendar (verified 2026-09-26).

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