I believe IDFC concluded its partnership with Zerodha last year, if I'm not mistaken. Now, the 3in1 IDFC account is managed by ICICI securities. It might not be worthwhile, as mutual fund plans in all banks are regular. In the long term, there's a risk of losing a significant amount of money with this approach. I suggest sticking with the old account linked to your demat account, as we'll need to fund Zerodha before purchasing stocks. Direct debit from the bank isn't available.