OTM strike in BNF options

How’s the cut-off price calculated, to prevent trading in OTM options in Bank Nifty?

For example, I’m currently unable to buy BNF 24500CE (OCT Series) with BNF trading 23970. What price (or above) should be BNF trading at, for me to be able to buy 24500CE ?

Same thing applies for PE also. Below what price of BNF, can one buy 23500PE ?

Appreciate your response.


I faced the same problem when I tried to sell BNF 22500 PE in Nov 30 Expiry. The error message is: "“RMS:Rule: Option Strike price based on Ltp percentage for entity account across exchange across segment across product”

I am unable to understand this. What is the logic? If BNF is trading at 24000, why is selling 22500 Puts in November monthly expiry blocked?

I called Call and Trade and the person kept giving different reasons like expiry (makes no sense as today is a Monday), STT (which makes no sense since option is deep OTM), broker-wise limits by exchange (again makes no sense) and finally blamed RMS team

He infact recommended that I choose strikes that are closer to the market price. When I told him that that increases risk both for me and for ZeroDha, he didn’t have any answer.

@nithin, Could you please explain the logic?