The main difference between a payroll company and an employment agency is the recruitment of the employees. With a payroll company, the employer will take care of the recruitment and selection of the new employee itself. But everything that has to do with legal employment, such as salary, pension, premium and tax, is regulated by the payroll company. The employer does not have to deal with all administrative tasks itself. For example, if you become ill, the payroll company will pay you your hours.