I noticed that with about a week until expiration, a deep itm option on the s&p index xsp has about $15 more time value than the same strike put, I guess due to interest rates? Would being long a future instead of the deep money option have any cost savings, or would the future also decline in price by about $15 in a week because of interest rates? When looking at the different expiration's of ES futures, they only seem to be about a quarter point different, which I would have thought would be a lot more if interest rates are affecting the futures. Thanks.
If you post specific example of the comparison you are focused on, it will likely be possible to obtain a response enabling a clear understanding of the specific case(s)!
for example xsp market price of 322, the Jan 10th 310 call trading ~12.30 while the 310 put trading ~0.15 Those are a general idea of how it was trading. So why the extra 0.15 for the call over the put in time premium?
Huh? Is your question really: Why is the Extrinsic value of a CALL not identical to that of the corresponding PUT? Also, partially related, you may wish to consider the increased BID/ASK price of the ITM option, which is typically not Balanced, to produce a nice MID price! If I have misunderstood, please reply with additional info.
(C-P)=(k-k_forward) , (C+P)-(C-P)=2*timevalue(k) where () means take the absolute value. its the forward versus spot but it is an effect of considerable interest.