Has anyone tried to borrow from a box spread with Schwab?

[Fxmove88]

It's important to set the boxes as last to be liquidated. Though this is not guaranteed by IB's auto-liquidation algorithm.

 

[Sig]

Having several bad experience with Schwab, I am not positive if Schwab would let you trade better on a box than with IBKR. More expensive is a likely yes.

I would think that you should not have the exact same but opposite legs on two boxes in your account. They may cancel each other and cause problems. Choose completely different strike prices & expiry dates for different boxes.

Actually Schwab is cheaper for SPX trades, at least as far as commission goes, than IB because they have a fixed price while IB has a commission plus exchange fees structure and the SPX exchange fees are expensive.