After graduating from college, de Jongh returned to the Virgin Islands. He worked for several years with the Tri-Island Economic Development Council, during which he helped receive funding for the preservation of historic Virgin Island buildings, before taking a job with Chase Manhattan Bank. De Jongh first worked as an executive in the company's Puerto Rico office before returning to the Virgin Islands after earning the position of Consumer Manager of Operations in the U.S., British Virgin Islands and Saint Maarten. Under his leadership, Chase placed more emphasis on personal over corporate banking in the Caribbean and increased home mortgage lending.