The number of digits may differ based on which depository your account is from. In case of a CSDL, the account number will have 16 numeric digits. Whereas in case of NSDL the number will start with the letters ‘IN’ followed by 14 numeric digits.

In case you have misplaced your Demat account number, you can call up your Depository Participant’s customer care number and they can help you recover it.