Diagonal Spread Pro

When you buy a single option, theta decay works entirely against you - you lose value daily just from time passing. A diagonal spread converts theta from enemy to ally. By selling a shorter-term option, you collect time decay while your longer-term option decays more slowly. The trade-off is capped profit potential and requirement for price to move toward a specific target (the short strike) rather than just 'in your direction.'

No, your maximum loss is strictly limited to the net debit paid. This is a key advantage of diagonal spreads - they provide defined risk. Even in worst-case scenarios (market crashes or spikes against you), your loss cannot exceed the initial premium paid. This makes diagonals suitable for traders who want directional exposure with controlled downside.

Diagonals offer three advantages over verticals: 1) Positive theta - time works for you, not against you, 2) Positive vega - you can benefit from IV increases, 3) Rolling potential - you can sell multiple short options against the same long option, potentially recovering cost many times. The trade-off is complexity and requirement for more precise price targeting.

Diagonal spreads are capital-efficient since they're debit strategies. For FTSE 100 diagonals, expect roughly £1,000-£2,000 net debit per contract (at £10 per index point) depending on strike width and expiry selection; single-stock option contracts are smaller. A recommended minimum of around £15,000-£20,000 lets you run 2-3 diagonal positions while keeping each under 10% of capital. This allows proper diversification and risk management.

If the underlying moves past your short strike (in your direction), your profit increases up to a point, then starts to decrease because the short option gains intrinsic value faster than the long option. You have options: 1) Roll the short strike further out to capture more upside, 2) Close the entire position at partial profit, 3) Let front month expire and manage long option separately. The key is having a plan before this happens.

Use calendar spreads when you're neutral - expecting price to stay near current level. Use diagonals when you have directional bias but want to benefit from time decay. Calendars have peak profit at one strike; diagonals have skewed profit curve favoring your direction. If your view is 'slightly bullish with the FTSE 100 moving to 8,500,' diagonal is appropriate. If your view is 'the FTSE 100 will stay near 8,400,' calendar is better.

Consider rolling when: 1) You've captured 40-50% profit and expect continued favorable conditions, 2) Your directional thesis remains intact, 3) Roll can be done for credit or minimal debit, 4) Back month still has 25+ DTE remaining. Close instead when: 1) Captured 60%+ profit, 2) Thesis has changed, 3) Roll would require significant debit, 4) Back month has less than 20 DTE. When in doubt, take profits - a closed profit can't become a loss.

Assignment is not a concern for FTSE 100 index options, which are European-style and cash-settled. UK single-stock options on ICE/LIFFE are American-style and physically settled, so early assignment on an ITM short leg is a real risk (Eurex single-stock options are European-style). If assigned on a short call you would need to deliver shares you don't own - your long call lets you exercise to obtain them, but early assignment disrupts the strategy. Close ITM short legs 2-3 days before expiry to avoid.

Not directly, but you can adjust through rolling. If you want wider width (more aggressive), roll the short strike further OTM for a debit. If you want narrower width (more conservative), roll the short strike closer for a credit. You can also add another short option at different strike, creating a ratio diagonal. Each adjustment has trade-offs - evaluate based on current market view and position Greeks.

Risk no more than 5-8% of trading capital per diagonal. Total diagonal exposure across all positions should stay under 20% of capital. Calculate actual risk as: net debit x contract multiplier x number of contracts. For a £50,000 account: max risk per position = £4,000 (8%). If a FTSE 100 diagonal debit is 175 points (= £1,750 per contract at £10/point), max position = £4,000 / £1,750 = 2.3, so 2 contracts maximum.

For optimal PMCC: 1) Buy long call at 0.75-0.85 delta - high enough to minimize extrinsic value at risk, low enough to avoid paying excess intrinsic, 2) Select long expiry 60-90 DTE for cost efficiency (avoid premium decay), 3) Sell short call at 0.25-0.30 delta, 10-21 DTE for optimal theta/gamma balance, 4) Ensure short strike is above long's breakeven to avoid locked-in loss, 5) Target short premium of 8-12% of long option cost per cycle.

Low VFTSE (<13): Reduce position size, use narrower strikes, accept lower theta. Premiums are thin, and any vol spike benefits you. Moderate VFTSE (13-18): Optimal regime - use standard structure and sizing. High VFTSE (18-25): Increase position delta slightly (more aggressive short strikes) to capitalize on elevated premiums, but reduce position size for the inevitable vol moves. Very high VFTSE (>25): Consider avoiding or use very wide strikes with small size.

Diversify by: 1) Underlying - spread across the FTSE 100 index and select large-cap single-stock options with low correlation (noting single-stock liquidity is thinner), 2) Direction - maintain balanced book unless strong macro view, 3) Expiry timing - stagger expiries across the available weekly (FTSE 100) and monthly cycles, 4) Entry timing - don't enter all positions same day. Limit aggregate Greeks: total portfolio delta < +/-30% of notional, total vega exposure aligned with vol view. Correlation during stress events means less diversification benefit than expected.

Diagonal as hedge: If long stocks/futures, add a bearish put diagonal (FTSE 100 puts for an index hedge). The sold front month put reduces hedge cost; the bought back month put provides protection. Roll the front month repeatedly to finance the ongoing hedge. For a concentrated stock position: use a collar-like diagonal - sell an OTM call diagonal to finance an OTM put diagonal. This creates a low-cost hedge band with rolling income potential. Size hedge diagonals at 30-50% of underlying notional for partial protection.

Key metrics: 1) Win rate 55-65% (higher suggests taking profits too early; lower suggests poor selection), 2) Average win/loss ratio 0.8-1.2 (diagonals have capped profit, so slightly lower is acceptable), 3) Profit factor >1.3, 4) Maximum drawdown <20% of account, 5) Rolling efficiency - credit per roll / time extended ratio, 6) Gamma-adjusted returns - did profits come from theta or lucky directional moves? Track separately for different configurations and optimize those with proven edge.