Credit Spread

What Is a Credit Spread?

A credit spread is a two-legged strategy where the premium collected from the short option exceeds the premium paid for the long option, resulting in a net credit upfront. You receive cash at entry — the maximum profit — and the long option defines maximum loss regardless of how far the underlying moves.

The two primary types are the bull put spread (sell higher-strike put, buy lower-strike put, profit if underlying stays above the short put) and the bear call spread (sell lower-strike call, buy higher-strike call, profit if underlying stays below the short call). Both profit from time decay and favorable price movement.

Example (bull put spread, stock at $100):

• Sell the $98 put for $2.00
• Buy the $93 put for $0.75
• Net credit collected: $1.25 ($125 per contract)
• Max profit: $1.25 (keep full credit if stock stays above $98)
• Max loss: $3.75 (spread width of $5 minus $1.25 credit)

Why It Matters for Options Traders

Credit spreads are foundational to premium-selling strategies. The core appeal is that they put time decay (theta) on your side — unlike buyers who need the underlying to move, sellers need time to pass and the underlying to stay within a range. This gives sellers a statistical edge when implied volatility is elevated: the market overprices options, and selling that overpriced premium with defined risk captures that edge.

The risk/reward profile is inverted from debit spreads. Credit spreads collect smaller premium relative to potential loss (you risk more than you make), but carry higher probability of profit. A well-placed bull put spread may have 70-80% probability of expiring worthless — you collect full credit most of the time, accepting occasional larger losses.

Selecting the appropriate strike placement is the key decision. Closer strikes to the underlying price collect more premium but have lower probability of max profit. Further strikes have higher probability but collect less premium. Most traders use metrics like delta (a proxy for probability) or probability of touching to calibrate this tradeoff.

Key Characteristics

• Entry: Net credit received (cash flows into the account on entry)
• Maximum profit: Net credit collected, achieved if the underlying stays beyond the short strike at expiration
• Maximum loss: Spread width minus net credit collected
• Probability of profit: Typically 60-80% depending on strike selection
• Ideal environment: High implied volatility (premiums are rich); neutral to moderately directional outlook
• Greeks: Net positive theta (benefits from time decay), net negative vega (benefits from IV contraction)