Money Transfer Lockdown and ACH debits from a Fidelity CMA
I’m trying to better understand the practical value and limits of Money Transfer Lockdown on a Fidelity CMA.
My understanding is that MTL is useful because it can block certain outbound transfers from Fidelity, such as EFTs, wires, and transfers of assets (ACAT). That’s a real security benefit.
But it does not appear to be the same thing as an ACH debit block. In other words, if a biller has your Fidelity routing number and CMA account number, it may still be able to initiate a direct debit / ACH pull, even with MTL turned on.
That distinction seems important. A lot of us may think “Money Transfer Lockdown” means the account is broadly locked against money leaving, but ACH pulls seem to be a separate risk category. That's a very big security hole.
For now, I’m leaning toward using a regular FDIC-insured bank checking account for biller-initiated ACH debits and keeping the CMA routing/account number less exposed. The CMA can still be useful, but I don’t want to confuse MTL with a true ACH positive-pay or debit-block feature.
Am I understanding this correctly? Has anyone gotten a clear answer from Fidelity on whether there is any way to block all ACH direct debits from a CMA?