We have a customer with several business and personal accounts. He recently opened a business checking account for a single member LLC, using his individual SSN instead of an EIN. The customer wants to access all of his accounts through online banking, which would allow him to transfer funds between the personal and business accounts. Should we treat the LLC as a sole proprietorship?

No, we would not recommend treating the single member LLC as a sole proprietorship. Although the LLC has only one owner, it is a business entity that has a separate existence from its owner.