SPX vs SPXW Options: AM vs PM Settlement Explained

Reviewed by Leon Moyer - Published October 9, 2026 - Last reviewed October 9, 2026

SPX and SPXW are two sets of options on the same S&P 500 Index that differ in when they settle. Standard SPX options are AM-settled: they stop trading on the business day before expiration and settle on a value calculated from Friday's opening stock prices. SPXW options are PM-settled: they trade until the close on expiration day and settle on the closing value.

Everything else is the same. Both are cash-settled, European-style, and worth $100 per index point, so both pay their in-the-money value in cash and can only be exercised at expiration. If those terms are new, Cash-Settled Options and European vs American Options explain them.

What is the difference between SPX and SPXW options?

On many broker screens the two appear in the same S&P 500 options chain, with SPXW identified by its symbol root. The differences, from Cboe's SPX specifications and SPXW specifications:

The third Friday is the confusing day: an AM-settled SPX series and a PM-settled SPXW series can both expire then, at the same strikes. They are different contracts with different settlement values, so check the symbol root before you trade.

Brokers label the two in different ways, so learn where yours shows the symbol root before expiration week.

What does AM-settled mean for SPX options?

For an AM-settled option, the exercise settlement value, which Cboe calls SET, is calculated from the opening sales price of each component stock in its primary market on expiration morning. Trading in the expiring options ordinarily stops the business day before, usually Thursday.

That leaves a gap. After Thursday's last trade you can no longer buy or sell the expiring option, but its value is not decided until Friday's opening prices are in. Anything that moves the market overnight, such as economic data released before the open, news from abroad, or a surprise earnings report from a large company in the index, flows straight into the settlement value.

SET is also built from each component stock's own opening trade, not read off the index at a single moment, so it may not match the index level you see quoted around the open.

What does PM-settled mean for SPXW options?

For a PM-settled option, the settlement value is based on the closing prices of the index's component stocks on expiration day. Cboe's end-of-month SPX specifications describe it as "calculated using the last (closing) reported sales price in the primary market of each component stock."

Cboe's SPX specifications say trading in expiring SPXW options ordinarily ends at 4:00 p.m. ET on expiration day, and at 1:00 p.m. ET on a half-day holiday, so you can close or adjust a position right up to the end. Brokers may set earlier cutoffs of their own. Since Cboe added Tuesday and Thursday expirations in 2022, SPXW options expire every business day of the week. Same-day expirations, often called 0DTE options, are covered in the Short-Dated and 0DTE Trading module of this course.

For this long call: the maximum loss is the premium paid, $2,000. The maximum profit is unlimited in theory, because the settlement amount keeps rising with the index. The break-even is the strike plus the premium, 6,020.

Should you trade SPX or SPXW?

Both settle in cash on the same index, so the choice is mostly about timing. SPXW gives you a series for every business day and lets you trade until the closing bell on expiration day. Standard SPX is the third-Friday monthly series. Cboe's rulebook (Rule 4.13(b)) also allows index LEAPS on SPX that expire 12 to 180 months from issuance; check the chain for what is actually listed. Those are index LEAPS with their own rules; the equity LEAPS described in the LEAPS and Long-Term Options module (What Are LEAPS Options? Long-Term Options Explained) are a separate product.

Whichever you pick, three habits help:

• Know which one you hold. A third-Friday position might be either. Check the symbol root.
• Decide by Thursday. If you hold an AM-settled SPX option, Thursday's last trading session is your last chance to close it.
• Size for the gap. If you choose to hold into settlement, assume the settlement value can be meaningfully different from Thursday's close.