Option spread question.

Hello traders,
Please help on to understand margin requirements for Options trading (long term) in India.
What is the margin required if I want to buy 1 lot of calls for DEC 2013 and sell some other lot of calls for DEC 2013?

For example consider below scenario:
Strike - Bid/Ask - Expiry
5300 - x Rs - DEC 2013 - Sell 1 lot
5200 - y Rs - DEC 2013 - buy 1 lot

If I want to keep my position till option expiry.
Do I have to pay (y*50) i.e. buy price + Rs 17000 margin for sell?
I need to understand do brokers or NSE provide any additional discount if I buy + sell?

If you buy sell then you need to pay the higher amount. So in your example it will be 5300 - x Rs - DEC 2013 - Sell 1 lot. Also margin requirements will be changing say the market is at 5300 when you sell 5300 put, now when market moves to 5400 and above slowly your margin will be released back.

In india, you pay 7% to 8% of the total value as margin for Index options.
e.g Selling a Nifty Call of Strike 6000 means total value of trade is 50 x 6000 = 3lakhs
7 % of 3 lakhs is 21,000.

So you require a margin of 21k to sell this call. Also, if it is sold at Rs 50 , your account will get credited for 50 x 50 = 2500 /-.

So net net you will require 21000 - 2500 = 18500 for selling a call.

For buying, you require margin equivalent to premium multiplied by lot size.

For selling stock options , margins required are much higher ie. to the tune of 50k plus.