My large transaction report pulls in all accounts of IOLTA's as they have the same EIN. If they are for different lawyers, do I still need to aggregate the deposits for a CTR?

In that case I would aggregate by account instead of TIN.

But you would need to identify the lawyer's client in Part 1 Section A since it is he, not the lawyer, that is benefitting from the cash.

Actually, there should be two section A entries -- one for the attorney's client, and the other for the attorney (or law office), as the owner of the account. Don't forget to complete a Section B entry for the warm body that made the deposit.

This thread reminds me why I don't like the practice of assigning the IOLTA Committee's EIN to IOLTA accounts. For systems that aggregate at the TIN level, it causes problems. There is the problem illustrated in the lead question in this thread, and there is the problem of possibly missing a CTR if part of a day's cash deposits go to an IOLTA account and part to the law office's own account or to a separate escrow account under the law office's name.

There's also the problem that it complicates a bank's CIP, because the bank has to consider the law firm (or lawyer) the customer, and collect that person's TIN for CIP, even if the bank will use the IOLTA Committee's EIN for reporting.

It would be so much easier if the proper TIN for the customer is used, and the account is flagged not to create a 1099.

And yes, I know that some IOLTA regulatory bodies have rules that tell banks to use their EINs. I disagree with that rule, but I won't go so far as to advocate ignoring it when it's there.