Expiry: the day the maths changes

As expiry approaches, two Greeks go to war. Theta accelerates, rewarding sellers. Gamma explodes, punishing them for being wrong even slightly. Every expiry-day concept on this page is a consequence of that single tension. These are concepts, not systems — and certainly not signals.

What are expiry strategies? Expiry strategies are concepts built around how option Greeks behave as time to expiry approaches zero. Theta decay accelerates while gamma rises sharply, so small moves in the underlying produce disproportionate changes in an option's value. Weekly, monthly and zero-days-to-expiry contracts each express this differently.

Weekly Expiry

Direction-agnostic

Weekly Expiry refers to index option contracts that expire within days rather than a month, carrying less total time value but much higher theta and …

No fixed legs — a concept page about short-dated weekly contracts Defined

Monthly Expiry

Direction-agnostic

Monthly Expiry refers to index and stock option and futures contracts that expire at month-end, carrying more total time value, slower per-day decay,…

No fixed legs — a concept page about month-end contracts and rollover Defined

Zero Days to Expiry (0DTE) Concepts

Volatile

Zero Days to Expiry concepts describe the day a contract expires, when at-the-money gamma reaches its maximum and delta becomes a step function, so a…

No fixed legs — a concept page about the day a contract expires Undefined

Expiry Day Neutral Approaches

Neutral

Expiry Day Neutral Approaches are neutral option structures placed near the settlement zone on expiry, where the theta collected is a fraction of a m…

No fixed legs — a concept page about neutral structures on expiry day Undefined

Expiry Day Volatility Concepts

Volatile

Expiry Day Volatility concepts describe how realised and implied volatility behave on the final day — measured intraday volatility often rising into …

No fixed legs — a concept page about volatility behaviour on expiry day Undefined

Theta Harvest Concepts

Neutral

Theta Harvest concepts describe collecting option time decay through short-premium positions, and the honest accounting behind it — theta is not inco…

No fixed legs — a concept page about collecting theta and what it costs Undefined

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Frequently asked questions

What are expiry strategies?
Expiry strategies are concepts built around how option Greeks behave as time to expiry approaches zero. Theta decay accelerates while gamma rises sharply, so small moves in the underlying produce disproportionate changes in an option's value. Weekly, monthly and zero-days-to-expiry contracts each express this differently.
How many expiry strategies are there?
StrategyGyan documents 6 expiry strategies in full, each with a payoff diagram, its Greeks, its maximum profit and loss stated as a formula and as a worked number, and both NIFTY and BANKNIFTY examples.
Which of these has defined risk?
Weekly Expiry, Monthly Expiry carry a structurally capped maximum loss. Zero Days to Expiry (0DTE) Concepts, Expiry Day Neutral Approaches, Expiry Day Volatility Concepts, Theta Harvest Concepts do not — their loss is bounded only by how far the underlying can move.
Educational content only — not investment advice. See our Risk Disclosure.