A calendar spread, also called a time spread or horizontal spread, is an options strategy involving the simultaneous purchase and sale of two option contracts on the same underlying security. Both options have the same strike price but different expiration dates. Investors typically sell the near-term option and buy the longer-term option, creating a net debit or credit depending on market conditions. This strategy is particularly attractive to sophisticated investors seeking to generate income while managing risk exposure.
How It Works
The mechanics rely on the differential decay rates of options at different maturities. Options lose time value as they approach expiration, and this decay accelerates in the final weeks. By selling a short-term option with faster decay and owning a long-term option with slower decay, an investor captures the time value difference. If the underlying asset's price remains near the strike price, the short-term option expires worthless or with minimal value, while the longer-dated option retains significant premium. The investor can then repeat the strategy by selling another near-term option against the remaining long position.
Why It Matters for Investors
Calendar spreads offer several advantages for portfolio management. They provide income generation through the premium collected from selling shorter-dated options, reducing the cost basis of the longer-term position. This strategy works best in sideways or low-volatility markets where you don't expect dramatic price swings. It's also less capital-intensive than outright option purchases and provides defined risk parameters. For accredited investors managing concentrated positions or seeking tactical income, calendar spreads can complement a broader options trading program.
Example
Suppose a stock trades at $100 per share. An investor believes the stock will remain relatively stable over the next three months but could move significantly afterward. They might sell a one-month $100 call option for $3 (collecting $300 premium) while simultaneously buying a three-month $100 call for $5 (paying $500). The net cost is $200. If the stock stays near $100, the one-month call expires worthless, the investor keeps the $300 premium, and the three-month call retains value. The investor repeats this process monthly against the remaining long call position.
Key Takeaways
- Calendar spreads profit from time decay differential between options at different expiration dates
- Strategy works optimally when underlying asset price remains stable near the strike price
- Reduces overall cost of long option positions through premium collection from short-term sales
- Requires active management and understanding of implied volatility changes and Greeks to execute effectively