We ask each year that you submit a census of your employees but, interestingly enough, the question: "Who is an employee?" may arise.
Obviously a person receiving a W-2 is an employee and should be listed. If we receive a data feed from your payroll company it is implied that your census is complete and your job is done. But, there are circumstances and instances created by the governing Tax Law, and articulated in your Qualified Plan Document, that can cause what you would term as an "Independent Contractor"; a "Contract Employee"; a "Leased Employee"; or a "Temporary To Hire Employee" - folks that you don't consider to be an employee- to be deemed employees. Subsequently, being deemed an employee causes these individuals to become eligible for benefits under your retirement plan.
Also, it is the rule that if these folks make a change in status to an actual W-2 employee, then their "date of hire," as required by law, is the first date that they completed an hour of services as a "Non-Employee," it is not the date that they convert to an actual employee.
It is a "Best Practice" for Plan sponsors to learn, to review annually, and to know these definitions so that Employee Status is reported properly. Properly reporting Employee Status ensures that contributions and benefits for these folks are properly calculated. If you need assistance please contact your service team member!