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Leased Employees

Definition: Workers who are officially employed by a professional employer organization, which is responsible for overseeing all HR-related functions, but who actually perform all work for your company

Employee leasing is a contractual arrangement in which the leasing company, also known as a professional employer organization (PEO), is the official employer. Employment responsibilities are typically shared between the leasing company and the business owner (you, in this case). You retain essential management control over the work performed by the employees. The leasing company, meanwhile, assumes responsibility for work such as reporting wages and employment taxes. Your main responsibility is writing a check to the leasing company to cover the payroll, taxes, benefits and administrative fees. The PEO does the rest.

Employee leasing lets you add workers without adding administrative complexity.

http://www.entrepreneur.com/encyclopedia/leased-employees