Answered in detail here: What is the business model of Coin now that it is free? Also, does Zerodha sell client data or take money from AMCs? - #3 by nithin
No, there’s no STT, transaction charges etc. DP charges are waived off too. Exit load will be applicable in specific cases when you redeem, but this is charged by the AMC, no by Zerodha. Zerodha doesn’t charge you anything.