We have a customer who continues to structure cash transactions. Several $9,000 cash deposits and then they will get a cashier's check. This is pretty much the only thing the account is being used for. We'd like to close the account. What reason should we give the customer? Could it be a potential issue if we say we are closing it due to structuring?

You don't need to give them a reason. If you've provided them a CTR Brochure, they will probably get the hint. Your account agreement should say you can choose the exit the relationship at any time for any reason. You choose who you want to bank.

Giving a customer a reason for the bank's pulling the plug on their account(s) is an invitation for an argument. It can also lead to threats of lawsuits and other nasty stuff. Don't offer a reason. Most terminated customers know why they are getting the boot. And if they are structuring, they may be irked they were discovered, but they will know why they are being exiled.

We often use this general language in the notice of closure.

"The account activity does not match what was originally reported as expected activity.

As stated in your Account Terms and Conditions, “we may close the account at any time upon reasonable notice to you and tender of the account balance personally or by mail."

I would totally skip the first sentence. It really is a meaningless statement. Quote your depositor's agreement and be done with it.