Learn · options market structure
How do 0DTE options affect SPY?
Zero-days-to-expiration (0DTE) options expire the same day, so their gamma is very high near the money and their hedging needs change fast. Large 0DTE positions can create intraday walls and magnets that matter for hours, then vanish at the close. Their effect is strongest near heavily traded strikes late in the session.
Why gamma is so high
As expiration approaches, an at-the-money option's delta swings quickly between 0 and 1, so dealers must adjust hedges more often and in larger size for the same move.
What traders watch
The day's largest 0DTE strikes, which side of them price sits on, and the expected move for the day. GammaPulse's dashboard shows SPY's 0DTE walls alongside the all-expiration walls.
Limits
0DTE positioning turns over during the day, and open interest is reported once a day, so intraday estimates rely on volume as well.
Related
- What is the expected move and how is it calculated?
- Where is SPY's gamma wall today?
- How do options market makers move prices near expiration?
Education and market data, not investment advice. GammaPulse does not publish a track record or performance claims.