Box Spread

A box spread creates a synthetic loan using options, typically at rates near Treasury yields.

Structure

Buy:  Bull Call Spread (Buy lower strike call, Sell higher strike call)
Sell: Bear Put Spread  (Sell lower strike put, Buy higher strike put)
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Result: Guaranteed payoff of (Higher Strike − Lower Strike) × 100 at expiration

The cost to enter is less than the guaranteed payoff. The difference is the implied interest rate.

Example

Tax Treatment

• Qualifies as §1256 contract (SPX/XSP options)
• 60/40 long-term/short-term treatment
• Loss offsets capital gains on Schedule D
• Does NOT require itemizing (unlike margin loan interest)
• If no capital gains to offset: limited to $3,000/year against ordinary income; excess carries forward

Requirements

• Portfolio margin or Level 4+ options approval
• Use European-style index options (SPX, XSP) to avoid early assignment
• Significant capital requirement (SPX boxes require ~$100K+ margin)

Box spreads offer the lowest borrowing rate available to most individuals, but require sophisticated options knowledge.

Sources

• 26 U.S.C. §1256 – Section 1256 Contracts
• CBOE: SPX Options Product Specification
• IRS Form 6781 – §1256 Contracts and Straddles