A CMR (Client Master Report), sometimes called a CML (Client Master List), is a document your broker issues that contains your full demat account profile: name, BO ID, depository (CDSL/NSDL), DP name, PAN and linked bank details. It is effectively your demat account's "identity card".
Why it matters to you
Every unlisted-share seller or platform will ask for your CMR before transferring shares to you. It lets them populate the DIS accurately so the shares land in the correct account, and it confirms the account is in your name. Sharing a clean, current CMR is the fastest way to get a transfer moving.
Example: A delayed purchase was traced to a stale CMR with an old address; re-downloading the latest copy fixed it. See how to download your CMR on Zerodha, Groww or HDFC.