I want to see the margin impact from closing an option. But the Margin/Performance box is greyed out. I have been able to check margin before, but not sure why I can't now. I'm long and short about 25-30 different strikes on SPX expiring in June and July so it's possible that the tool can't calculate the margin impact, but I don't buy that as at any time, IB needs to know how much margin their customers have. I also tried checking via the option chain on an option that I don't currently have a position on. Still doesn't work:
The issue was because I had not indicated buy or sell so the order entry was not complete. Makes sense.