The last 15 minutes of a 0DTE session are a decision, not a drift. Whatever you're holding, three forces are converging: gamma is peaking, spreads are at their widest, and expiration — with auto-exercise — is minutes away. Hold, close, or flatten: pick deliberately.
Close (the default)
For most scalpers, most days, the answer is close the position for the current gain (or loss) and be done. You lock in the result before the spread widens further and before any settlement risk. A bird in the hand beats a few more cents of a decaying option into a thinning market.
Hold (rarely, with a reason)
Holding into the final minutes only makes sense with a specific thesis — a strong negative-gamma momentum move or a tight pin you're fading — and even then, you're paying a widening spread for the privilege. If you hold, know that in-the-money means it will exercise into shares unless you close it. Never hold a winner into settlement to save a commission.
The last 15 minutes charge the most to trade and offer the least liquidity. Closing is the default; holding needs a reason and an exit.
Flatten (the safety rule)
If you're unsure, flatten. There's no prize for carrying a same-day option to the bell, and the downside — a bad exit fill, an accidental ITM settlement into stock you can't fund — is real. This is exactly why NoVo keeps the last-15-minutes exit one click away: a live read into the final minutes and a one-click close, so banking the result and sidestepping settlement risk is effortless — the call is yours, but nothing about making it is hard.