Option newbie here. I was talking to my broker ToS regarding what would happen if the short put option was exercised early (yes I know it might be unlikely to happen), but I wanted to make sure I know what happens in the worse case scenario. Most places I've researched on the net and in books say the margin required and max loss is the difference between the strike price minus the credit received. However, after talking with my broker to see what would happen if the short put option was exercised early which would of course force me to buy the stock at the put price, but by having stock and an open long put I'd have a different set of margin requirements per ToS support as I would need enough money to buy the stock. This makes sense I suppose in that the margin requirements would change and I'd need enough money to cover buying the stock when the short put is exercised. However, my question is given that most books and examples on the net say your margin required is only the strike price diff - credit seems a bit misleading. And that's just the initial margin to initiate the trade, but to be fully covered you'd need enough money as if you were to buy the stock. This seems to defeat the purpose of using option and a spread to reduce the cost? I guess if you don't think about being exercised you can leverage your account and trade as many spreads as your account allows but could end up burnt if exercised with a margin call. So if I want to be ultra-conservative with my risk to avoid margin calls I won't be able to take advantage of any leverage with the initial margin required to make the trade. Am I missing something? Thanks in advance for any insight as I've been racking my brain all day about this.