Monthly Expiry
Monthly expiry options are index and stock contracts that expire once a month, carrying more time value and slower decay than weeklies — suited to positional trades, hedging and strategies that need room to play out.
In one line: Monthly expiry options are index and stock contracts that expire once a month, carrying more time value and slower decay than weeklies — suited to positional trades, hedging and strategies that need room to play out.
In simple words
Monthly options expire in the last week of each month. They cost more than weeklies because they have more time value, but they decay slowly until their final week. This makes them better for positional views, hedging a portfolio, and multi-leg strategies that need time. Stock options in India are monthly, while indices have both weekly and monthly contracts.
Visual
Monthly Expiry
A monthly option decays slowly for most of its life and only enters the steep part of the time-decay curve in its final week.
What monthly expiry means
A monthly option settles on the monthly expiry, which the NSE schedules in the last week of each month (the exact day is set by the exchange and revised periodically — check the current calendar). Indian stock (single-stock) options are monthly, and indices like Nifty and Bank Nifty have monthly contracts alongside their weeklies. With weeks of life, monthly options carry substantial time value and meaningful Vega, so implied volatility matters far more than it does for weeklies.
Slower, more forgiving decay
A monthly option spends most of its life in the gentle part of the time-decay curve, losing value slowly until the final week, when decay accelerates. This makes monthlies more forgiving for buyers — a thesis has room to develop without the premium evaporating in days. Positional traders and hedgers favour monthlies precisely because they are not racing an immediate clock, accepting a higher premium in exchange for time and stability.
More Vega, more volatility exposure
Because they have more time until expiry, monthly options carry significantly more Vega than weeklies. This means their value is more sensitive to changes in implied volatility — a rise in India VIX inflates monthly premiums more, and a fall deflates them more. Traders must therefore weigh the volatility environment when buying or selling monthlies, whereas weeklies are relatively insulated from Vega.
When to choose monthlies
Monthly options suit multi-week directional views, portfolio hedges that must last, and complex strategies (calendars, longer-dated spreads) that need time to work. They are also the natural choice for stock options. The trade-off is cost and slower gratification: you pay more premium and decay works more gently, in exchange for room to be right over a longer horizon and lower Gamma risk day to day.
Practical example (Nifty)
Illustrative — Nifty, lot size 75
You expect Nifty to trend up over the next three weeks and buy a monthly 20,000 CE for ₹350 with Nifty at 20,000. Over the first two weeks, even if Nifty moves sideways, Theta is gentle and the option holds much of its value — unlike a weekly, which would have expired. If Nifty climbs to 20,600 by the final week, the call is deep in profit. The higher upfront premium bought you time and slower decay for a positional view.
Monthly vs weekly expiry
| Monthly | Weekly | |
|---|---|---|
| Life | Up to a month | A few days |
| Premium | Higher | Lower |
| Decay | Slow until final week | Fast throughout |
| Vega risk | Higher | Lower |
| Best for | Positional / hedging | Short-term / expiry |
Why it matters in practice
- Monthly options carry more time value and decay slowly until the final week.
- They suit positional views, portfolio hedges and multi-leg strategies needing time.
- Higher Vega means implied volatility matters more than for weeklies.
- Indian stock options are monthly; indices offer both monthly and weekly.
Common mistakes
- Overpaying for monthly premium when a shorter-dated option would suffice for a quick view.
- Ignoring the higher Vega and getting hurt when implied volatility falls after buying.
- Assuming slow early decay lasts — the final week's Theta still accelerates.
- Holding in-the-money monthly stock options into expiry and facing physical settlement.
What professionals do
Skilled traders match expiry to horizon: they use monthlies for multi-week theses and hedges, appreciating the gentler decay and room to be right, while weighing the higher Vega against the volatility outlook. They roll positional monthlies before the final-week decay and settlement pressures bite, and they always close in-the-money monthly stock options before physical delivery is triggered.
Key takeaway
Monthly expiry options offer more time value, slower decay and higher Vega than weeklies — ideal for positional trades, hedges and complex strategies. You pay more premium for room to be right over weeks and lower day-to-day Gamma risk.
Frequently Asked Questions
What is monthly expiry in options?
What is the difference between monthly and weekly options?
Are stock options weekly or monthly in India?
Why do monthly options cost more than weekly?
When do monthly options decay fastest?
Do monthly options have more volatility risk?
Are monthly options better for beginners?
When is monthly expiry in India?
Should I roll a monthly option before expiry?
Sources & references
Educational content only — not investment advice.