I have a customer who used his personal account without available funds to negotiate checks at another bank, into his business account. Two days later the customer gets an ACH credit into his personal account from the business account at the other bank for the same amount of the checks that were negotiated. Kiting through ACH!

Anyway, do I need two separate SARs? One for the individual and one for the business? Or just one on the individual and note everything in the narrative?

I would just do one and describe all cirumstances including both accounts.

A SAR describes 'Suspicious Activity' and not just 'Suspicious Transactions' It seems as though all of the scenarios involved constitute the former, and are somewhat of the basis for your suspiciousness determination. As such, one SAR is all that would be required.

It is related - in fact it would not be kiting without both parts - so report it together in one SAR. The story would not make much sense if reported separately.

thank you!