The Demat Account Opening is Free but the AMC is applicable as mentioned below:
For existing clients, the Demat AMC is ₹300 + GST ( ₹ 88.50 Quarterly)
For New clients, ₹225 + GST in 1st year. ₹300 + GST from 2nd year onwards.
You can refer to this article for more info on AMC and Our charges for Demat services are mentioned in the Charges List. You can also find these charges in the tariff sheet of the Demat account opening forms which are available in the Downloads.