Thanks - I saw these regs, but couldn't find a situation on single person S-Corps.   Wages to 2% Officers are exempt or optional in some states from unemployment registration.    The FL regs say:

"Any officer of a corporation performing services for the corporation is considered an employee during their tenure of office, regardless of whether compensation is received. Compensation, other than dividends on shares of stock and board of director fees, is presumed to be payment for services performed."

Also, as exempt, not covered:

"Services by a sole proprietor, a partner, or a member of a limited liability company classified for federal income tax purposes as either a partnership or a sole proprietorship."

The FL DOR Rep told me on the phone that they see single person S-Corps as Sole Prop, no registration required according to the second quote.   I didn't agree, and called another rep and was told registration was required since the person is "Any Officer" (per the first quote above).   Given the FUTA credit, I'll just go ahead with the and register the client.