A two-timeframe trade. Sell the near-month option, buy the far-month at the same strike, and profit from the faster decay of the short leg plus rising IV on the long.
A Calendar Spread is an elegant trade that exploits the difference in how options of different expiries decay. Time-value (extrinsic) in the near-month option melts much faster than in the far-month option of the same strike — so selling the near and buying the far gives you a positive-theta structure with a long-vega kicker.
Unlike an iron condor, a calendar is directionally forgiving around the strike and actively benefits from a rise in implied volatility. Its ideal environment is a low-vol regime that you believe will revert — the long leg holds IV while the short leg dies into its expiry.
The trade-off is sensitivity to the spot-strike distance. If spot moves meaningfully away from the strike, both legs lose intrinsic-adjusted value, and the short leg's decay advantage disappears. Sizing and strike placement matter a lot.
Two calls (or two puts) at the same strike, different expiries. Sell the near-month, buy the far-month. The further the expiries are apart, the more time-value differential you capture — but also the bigger the net debit.
| Action | Instrument | Strike / Expiry | Premium (est.) |
|---|---|---|---|
| Sell | Nifty Call (near) | 22,500 CE · weekly | 90 |
| Buy | Nifty Call (far) | 22,500 CE · monthly | 170 |
| Net debit | 80 (= ₹6,000 per lot of 75) | ||
The calendar is one of the rare structures that is simultaneously positive-theta and positive-vega — a rarity that makes it especially attractive when IV is cheap. Just remember the gamma profile sharpens dangerously as the near-expiry approaches.
Nifty spot at 22,500. You sell the near-weekly 22,500 CE at ₹90 (4 days to expiry) and buy the monthly 22,500 CE at ₹170 (25 days to expiry). Net debit = ₹80 × 75 = ₹6,000 per lot.
The payoff at the near-expiry depends on how much extrinsic remains in the long leg. If spot pins exactly at 22,500 at the near-expiry, short goes worthless, and the long leg might still be worth ~₹130 (20 days of extrinsic) — a gross profit of ₹130, minus the debit of ₹80 = ₹50 × 75 = ~₹3,750 profit.
Actual values at near-expiry depend heavily on implied volatility of the long leg — reinforcing why this is a vega-sensitive structure.
Options traders who understand IV term structure, vol-arb-curious learners, and anyone who wants to graduate beyond single-expiry structures. The calendar teaches you to think in two dimensions simultaneously — strike distance and time distance — which is the mental model that separates beginner options traders from intermediate ones.
See which timeframe style suits you best — take the Trader Quiz.
Calendars are subtle — the Greeks shift faster than you expect near the near-expiry. Paper-trade at least a full monthly cycle before committing capital to a live calendar.