What does an employee status of "not on payroll" mean?What status do I select for someone that works on call only once or twice per year and is currently inactive?

Hello Quinoa, 

Thanks for reaching out to us here. QuickBooks offers a flexible payroll program that enables you to manage your work with peace of mind. I'll be happy to provide the info you need in regards to your payroll.

Not on payroll pertains to an employee that you plan on re-hiring at any given time. This saves you from having to add the employee again. In case you'd like to reactivate the employee, you can do this by  following this article that shows you how to: Make an inactive employee active in QuickBooks Online Payroll.

Let me know if this info helps. I'll be one message away in case you need anything else.