🎯 What is Expiry Date in Options? (Simple Definition)
Expiry date is the last day when your option contract is valid. After expiry, the option expires worthless if it's out-of-the-money, or gets automatically exercised if it's in-the-money.
Think of expiry date like a movie ticket with a date. After that date, your ticket (option) is no longer valid. You must use it before expiry or lose it.
Key Point: In India, Nifty and Bank Nifty options expire on the last Thursday of every month. Weekly options expire every Thursday.
📅 Nifty Expiry Dates in India (2025 Calendar)
Monthly Expiry (Last Thursday of Month):
- • January 2025: January 30, 2025
- • February 2025: February 27, 2025
- • March 2025: March 27, 2025
- • And so on...
Weekly Expiry (Every Thursday):
Nifty and Bank Nifty also have weekly expiry options that expire every Thursday. These are popular for intraday and short-term traders.
⚖️ Weekly vs Monthly Expiry: Which to Choose?
📆 Weekly Expiry
Best For:
- • Intraday traders
- • Short-term strategies
- • Lower premium cost
- • Quick profit/loss
Risk: Faster time decay
📅 Monthly Expiry
Best For:
- • Swing traders
- • Position traders
- • Higher premium but more time
- • Less time decay pressure
Risk: Higher premium cost
⏰ Time Decay (Theta) Explained
What is Time Decay?
Time decay (theta) is the loss of option value as expiry approaches. Options lose value every day, even if stock price doesn't move. This accelerates in the last week before expiry.
Example: You buy Nifty Call for ₹150 with 15 days to expiry. Even if Nifty stays at same price, option value decreases daily. By expiry day, if price hasn't moved, option may be worth ₹0.
Time Decay Timeline:
- • 30+ days to expiry: Slow decay
- • 15-30 days: Moderate decay
- • 7-15 days: Accelerating decay
- • Last 7 days: Rapid decay (avoid buying here!)
🎯 How to Choose the Best Expiry Date
✅ For Beginners: 15-30 Days to Expiry
Gives you enough time for price to move while avoiding rapid time decay. Best balance of cost and time.
⚡ For Intraday: Weekly Expiry
Cheaper premiums, quick exits. Perfect if you plan to exit same day or within 2-3 days.
📈 For Swing Trading: Monthly Expiry
More time for your trade to work. Less time decay pressure. Higher premium but better for longer moves.
❓ Frequently Asked Questions
When do Nifty options expire in India?
Nifty monthly options expire on the last Thursday of every month. Weekly options expire every Thursday. Check NSE website for exact dates.
What happens to my option on expiry date?
If ITM: Automatically exercised (Call) or assigned (Put). If OTM: Expires worthless. You lose only the premium paid.
Can I sell my option before expiry?
Yes! You can sell (square off) your option anytime before expiry. Most traders do this instead of waiting for expiry.
What is the best expiry for beginners?
Start with monthly expiry options with 15-30 days remaining. Avoid buying options with less than 7 days to expiry due to rapid time decay.
Practice Expiry Date Selection Risk-Free
Test different expiry dates on Zerroday. Learn how time decay affects your trades with real Nifty data and AI feedback.
🚀 Start Free Paper Trading