Options Academy
Cash Secured Puts 103: Selecting the Strike
Which strike should you sell? ATM for max income? OTM for safety? We introduce "Delta" as your probability compass.
Delta: The Probability Gauge
Delta is not just a sensitivity metric; it is a rough proxy for "Probability of expiring In-The-Money".
-0.50 Delta (ATM): 50% chance of assignment. Max Premium.
-0.30 Delta (OTM): ~30% chance of assignment. The "Standard" choice.
-0.10 Delta (Deep OTM): ~10% chance of assignment. High win rate, low income.
Implied Volatility (IV) & Skew
Not all 30 Deltas are equal. You want to sell when IV is HIGH.
Put Skew: The market is typically more afraid of a crash than a rally. Institutions buy OTM Puts as "Crash Insurance".
Therefore, OTM Puts trade at higher IVs (and higher prices) than equidistant OTM Calls. This "Fear Premium" means put sellers are structurally overpaid over the long run.
Days to Expiration (DTE)
Why 30-45 days? Because of Theta (Time Decay).
Option value decay accelerates in the final 45 days. By selling the 45-day put and buying it back at 21 days, you capture the steepest part of the decay curve while avoiding the "Gamma Risk" of expiration week.
Key takeaways
- Use Delta to choose your risk level (-0.30 is standard).
- Sell into High IV environments to capture the "Fear Premium".
- The 30-45 DTE window offers the best balance of Theta decay and stability.
- Avoid holding until expiration day (Gamma Risk) unless you WANT assignment.
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