Weekly and daily options
Weekly options are short-dated listed options that expire on days other than the standard monthly third Friday; on the major US index products they now exist for every weekday, which is what makes 0DTE trading possible every session. They concentrate gamma and theta in the days before expiry and fragment open interest across many expiries.
Senzoukria · Glossary · Updated September 2026
At a glance
- SPX
- SPXW series listed for every weekday, PM-settled
- Main feature
- Very short time to expiry: high gamma and theta near the money
- Consequence
- Open interest spread over many expiries
What they are
Weekly options, often called weeklys, are ordinary listed options with short lives and non-monthly expiration dates. On the S&P 500, Cboe's SPXW series expire every weekday and settle on the closing value, so an option expiring today exists on every trading day. ETF and futures options have followed the same path: short-dated series on SPY and QQQ, and weekly options on E-mini index futures listed by CME for several days of the week. The contract terms are otherwise those of the product, including multiplier, exercise style and settlement method.
Why short-dated series behave differently
With a few days left, an at-the-money option has high gamma and high theta and almost no vega. With spot at 100, 20% implied volatility and zero rates, the 7-day at-the-money option has a gamma of 0.144 against 0.070 for the 30-day option, and loses 0.079 a day against 0.038. Its value depends mostly on where price goes in the next sessions, not on changes in implied volatility.
| Days to expiry | Gamma | Theta per day | Vega per vol point |
|---|---|---|---|
| 7 | 0.144 | −0.079 | 0.055 |
| 30 | 0.070 | −0.038 | 0.114 |
Consequences for positioning models
- Open interest spread over many expiries means that no single monthly series summarises positioning; the scope chosen for a GEX calculation changes the result.
- Short-dated gamma dominates intraday exposure near spot, and it disappears at each daily expiry, so levels are recomputed on a different book every morning.
- Much short-dated volume opens and closes within the day and never appears in the next day's open interest, so flow and open interest tell different stories.
In Senzoukria
The GEX module computes, beside the full chain, separate level sets for the nearest and the next expiry, and the Calculation assumptions panel can include, exclude or isolate same-day expiries when the nearest one is today. Option Flow deliberately restricts its contract list to the two nearest expirations and strikes within ±10% of spot, which covers same-day and next weekly series where most short-dated prints occur. Its table prints days to expiry computed on the New York calendar, so a contract expiring at today's New York close is labelled 0DTE even for a trader in another time zone.
Related
In the same section
- Why dashboards disagree
- Wash trading
- Win rate
- Walk-forward
- Withdrawn vs executed
- VWAP bands
- Working order
- VWAP
Sources
- Cboe — S&P 500 index options product specifications (2026-09-25)
This page in other languages
Frequently asked questions
- Are weekly options riskier than monthly options?
- They carry different risks. Their low price and high gamma make them react sharply to moves in the underlying and lose value quickly when price stalls, while monthly and longer options react more to changes in implied volatility. Position size relative to account matters more than the label.
- Do weekly options change how gamma exposure should be read?
- Yes. Because most near-the-money gamma now sits in the shortest expiries, a gamma figure depends heavily on whether today's expiry is included and changes shape through the session as that expiry decays. Always read a level together with its expiry scope and timestamp.