Usually, brokers offering a ‘zero brokerage on loss’ or ‘pay only when you profit’ plans take the average market price of the open position when you are squaring off the intraday trade. If you are losing money, then there will be no brokerage charged. While regulatory and statutory charges will apply, the ‘pay only when you profit’ plan ensures that your losses are minimized when the stock price does not move as anticipated by you.