I would like to ask about buying option spreads on futures. In stock options when you buy a debit spread you just pay the whole amount and that's it. No margin required. What about futures options? Let's say I have a $10,000 trading account and buy, for example, calendar spread on ES for $500, how much money from my account will be frozen? Who use futures options platforms or Interactivebrokers please check the margin requirements for debit spreads on ES, NQ, ZN.