What Is an Iron Butterfly?
An iron butterfly is a four-leg options strategy that combines a short straddle with protective wings. You sell both an at-the-money call and an at-the-money put at the same strike price, then buy an out-of-the-money put below and an out-of-the-money call above for protection. The result is a credit spread that profits maximally when the stock closes exactly at the short strike at expiration.
Compared to an iron condor, the iron butterfly generates a larger credit (because the short options are ATM rather than OTM) but has a narrower profit zone. It is essentially a high-risk, high-reward version of the iron condor. The strategy is best suited for stocks that are expected to remain very close to a specific price level, such as pinning behavior near options expiration.
Iron Butterfly Formulas
- 1Net credit = ($3.00 + $3.25) - ($0.75 + $1.00) = $4.50 per share
- 2Max profit = $4.50 × 100 = $450
- 3Wing width = $5.00 (both sides equal)
- 4Max loss = ($5.00 - $4.50) × 100 = $50
- 5Upper breakeven = $100 + $4.50 = $104.50
- 6Lower breakeven = $100 - $4.50 = $95.50
- 7Profit zone: $95.50 to $104.50 (9-point range)
- 8Risk/reward = 1:9 (risk $50 to make $450)
Iron Butterfly vs. Iron Condor
| Feature | Iron Butterfly | Iron Condor |
|---|---|---|
| Short strikes | Both ATM (same strike) | Both OTM (different strikes) |
| Credit received | Higher | Lower |
| Max profit zone | Narrow (single price point ideal) | Wide (range between short strikes) |
| Probability of max profit | Very low | Moderate |
| Probability of any profit | Moderate to high | High |
| Gamma risk | Higher (ATM shorts) | Lower (OTM shorts) |
| Best for | Pinned/range-bound stocks | Broad range-bound markets |
Iron Butterfly Setup Guide
- Iron butterflies generate the highest credit of any defined-risk options strategy
- The narrow profit zone means the win rate is lower than iron condors
- Best used with 14-30 DTE when Theta decay on the ATM shorts is accelerating
- Works well on high-IV stocks where ATM premiums are inflated
- Can be adjusted by widening wings or moving the center strike
You can create a 'broken wing' iron butterfly by using unequal wing widths. For example, a narrower put wing and wider call wing creates a bullish bias while maintaining a credit. This lets you customize the risk profile to your directional view.
Because both short options are ATM, the iron butterfly has high Gamma risk. Near expiration, small stock moves can swing the P&L significantly. Consider closing the position 5-7 days before expiration to avoid the Gamma knife effect.