Effective trade date November 9, 2026, Cboe Options Exchange (C1) will begin to roll out S&P 500 Index (SPX) AM-settled-Weekly options, subject to regulatory review.

The underlying index for the new expirations will be SPX and the trading symbol will be SPXO.

Similar to AM-settled SPX options that expire on the third-Friday of the month, SPXO AM-settled options will expire at the opening of trading on their expiration date and will settle to the SPX opening settlement price (SET).

The allocation algorithm for the single leg and complex books will be price-time for SPXO. The allocation method for symbol SPX will remain pro-rata. Additionally, SPXO quotes priced greater than $0 will have a minimum quote size requirement of 1, while the minimum quote size requirements for symbol SPX remain unchanged.

Symbol SPXO will reside on matching unit 33 along with symbol SPX.

Current SPX risk rules will automatically apply to SPXO. As a reminder, TPHs can configure separate risk limits for SPXW and SPX, even though they share the same underlying symbol (SPX) due to the fact that SPXW exists on a separate Matching Engine than SPX. TPHs will not be able to configure separate risk limits for SPXO.

Complex orders are permitted with any combination of options across symbols of any two of SPX, SPXO, and SPXW. However, complex orders are only able to execute by legging into the single-leg books if all of the single-leg books are on the same matching unit. Thus, complex orders with a combination of SPXW and either SPX or SPXO options will not be permitted to leg into the single-leg books because those books are on separate matching units.

SPXO shares the same trading schedule as SPX Options, including participation in Global Trading Hours (GTH). On the final trading day prior to an SPXO series’ AM settlement (expiration), trading in that series will cease at 4:00pm on regular trading days and will not resume for that evening’s GTH session.