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Key Takeaways
- An index option uses a specified index settlement value to determine its cash payout.
- SPX and XSP use European exercise; OEX uses American exercise.
- The SPX example pays 100 dollars per index point of intrinsic value.
- A 5,000 call bought for 40 points breaks even at 5,040 and earns $3,500 at settlement 5,075.
- Traditional SPX and SPXW expirations use different opening or closing settlement calculations.
- Qualifying listed broad-based index options fall within the Section 1256 nonequity-option category.
What is an index option?
An index option is an option contract tied to a calculated index value, such as the S&P 500 Index, rather than to shares of a stock or ETF. Its exercise settlement transfers cash according to the contract’s index reference, strike and multiplier, so no shares change hands.
For a call, payout is the positive difference between settlement level and strike, multiplied by the contract multiplier. For a put, reverse that difference. Subtract the entry premium to calculate the long position’s profit.
Formula
Cash settlement per call contract = max(settlement level − strike, 0) × multiplier; per put contract = max(strike − settlement level, 0) × multiplier- The multiplier for standard S&P 500 index options is 100, so one point of intrinsic value is worth $100 per contract.
- The settlement level is a specified index value at expiration, not necessarily the last traded price.
- No shares change hands; the in-the-money amount is credited or debited in cash.
Index option example: one SPX call
A trader buys one SPX 5,000 call for 40.00 points when the index trades near 4,990. SPX index options use a 100 multiplier and are European-style, so the position can only be exercised at expiration.
- Premium paid: 40.00 × 100 = $4,000 for one contract
- Suppose the settlement level is 5,075 at expiration
- Cash settlement: (5,075 − 5,000) × 100 = $7,500
- Net result: $7,500 − $4,000 = $3,500 before fees
At the stated 5,075 settlement value, the call pays $7,500 in cash. Subtracting the $4,000 premium gives $3,500 profit before transaction costs. The SPX contract uses European exercise and cash settlement.
Buy one SPX 5,000 call for 40 points. The $100 multiplier makes the premium $4,000. A settlement level of 5,075 produces 75 points of intrinsic value, or $7,500 cash.
Profit is $7,500 minus $4,000, totaling $3,500. Breakeven is 5,040. A settlement level at or below 5,000 produces zero payout and a $4,000 option loss.
Index option exercise style and settlement value
SPX and XSP are European-style contracts. OEX is American-style. Exercise style determines when the right is available; cash settlement determines what is transferred when it is exercised.
Traditional AM-settled SPX uses the SET calculation based on component opening prices. SPXW uses its specified closing-price calculation. Read the exact series, last trading time and settlement reference together.
Index option contract size: SPX, XSP and ETF options
At SPX 5,000, one standard contract has $500,000 underlying notional. XSP represents one-tenth of the index level, so at XSP 500 its $100 multiplier produces $50,000 notional.
Delta converts that notional into current directional exposure, so compare strikes and expirations on the same delta-adjusted basis. Standard ETF options instead reference ETF shares and use their own exercise and delivery terms.
Options flow and gamma exposure show activity and contract concentrations around index levels, and the options profit calculator compares a structure’s entry price, expiration payoff and price scenarios.
How are broad-based index options taxed?
For tax records, identify the contract’s classification. Qualifying listed broad-based index options are Section 1256 nonequity options, whose general capital-gain treatment uses a 60/40 allocation and year-end mark-to-market. Keep that record alongside the trade’s cash settlement and transaction costs.
Limitations of index options
- Map the payoff to the settlement value. AM-settled SPX uses the SET calculation from component opening prices, so an overnight gap moves the payout after the prior close.
- Size SPX positions from notional value. One SPX contract at 5,000 carries $500,000 of underlying notional, and each index point is worth $100 per contract.
- Exercise style varies by product. SPX and XSP are European-style while OEX is American-style, so the exit plan depends on the exact contract.
- Section 1256 treatment applies only to qualifying listed broad-based index options, and its year-end mark-to-market recognizes gains and losses on positions that are still open.
Bottom line
An index option gives exposure to an index level and settles the in-the-money amount in cash, with no shares changing hands. Before trading one, confirm its multiplier, exercise style, settlement series and last trading time, size the position from its notional value, and record whether it qualifies for Section 1256 treatment.
Clear answers
Frequently Asked Questions
Sources and Further Reading
- Cboe: OEX specifications
- Cboe: SPX specifications
- OIC: Equity vs. Index Options
- Cboe: S&P 500 Index Options (SPX)
- Cboe: Mini-SPX (XSP) Cash Settlement
- IRS Publication 550: Section 1256 Contracts Marked to Market
How entries are sourced, calculated and updated: editorial methodology.