The full Greek family is large, but on 0DTE only some higher-order Greeks matter. Here’s the honest guide to which ones actually move your expiration-day trade — and which you can ignore.

What dominates on 0DTE

Gamma is king — it’s at maximum, so delta swings hard and moves are sharp. Charm matters a lot — delta decay drives the pin into the close. Color (and speed) explain why gamma itself goes extreme late in the day. These time-and-price Greeks rule the 0DTE tape.

What barely matters on 0DTE

Vega and its higher-order cousins (vanna, vomma, veta) are small on 0DTE — there’s almost no time left for volatility to affect the option (that’s veta at work). So an IV move barely touches your 0DTE P&L, and the IV crush that hurts monthlies has little to bite on. Your 0DTE outcome is delta and theta.

On 0DTE, trade gamma and time — not volatility. Vega and its cousins have almost nothing left to move on expiration day.

The takeaway

For 0DTE, focus on gamma (sharp moves), theta (fast decay), and charm (the pin) — and don’t worry much about vega-family Greeks. That’s why 0DTE is a pure direction-and-time game. Note that at the dealer level, vanna/charm flows still shape the tape (they act on dealers’ whole books, not just your one 0DTE) — which is the structure NoVo maps.