Generally, employees are paid at a set rate, either on an hourly or salary basis. In the United States, employers are obligated to pay Social Security, Medicare, workman’s compensation, state, federal, and often local taxes for each employee. An employer also must deduct a portion of these taxes and other fees from the employees’ paycheck, and all of these transactions must be recorded for auditing and tax purposes.

A payroll service is a company that will, for a fee, handle all of these functions independently, freeing up the business owner's time for more important matters. Once an account is established, the employer simply provides the service with a list of all employees, the hours they worked, and any variances. This data is then processed and the funds are transferred from the employer's bank to the payroll service's account. Employees are paid either by standard check or direct deposit. The employer is then provided with payroll and tax reports.