All stock options expire on the last “Thursday” of the month of expiry.
Different weekly options on the other hand expire on different days as follows:
INDEX | DAY OF EXPIRY |
MIDCAP NIFTY | EVERY MONDAY |
BANKEX | EVERY MONDAY |
FINNIFTY | EVERY TUESDAY |
BANKNIFTY | EVERY WEDNESDAY |
NIFTY | EVERY THURSDAY |
SENSEX | EVERY FRIDAY |