Ronpak was founded in 1947 by Mr. Nathan Sedley, more about his innovations to the packaging industry are found below.

Ronpak was founded in 1947 by Mr. Nathan Sedley in New York City. At the time of the company's founding, Mr. Sedley was a practicing pharmacist. He recognized the need for retail packaging and purchased equipment to manufacture bags during a trip to Europe. His bags were an instant hit. Recognizing that a golden opportunity existed, Mr. Sedley left the pharmacy business and founded Ronpak.

In the years that followed, the company expanded its product line and marketed it to other retailers, in the hopes that they will take advantage of the custom printed aspect of Ronpak for advertising and promotional reasons. The company continued to grow and it became clear that Ronpak needed a larger plant to support its rapidly expanding business. Therefore, in 1956, the company built a 90,000 square foot manufacturing facility in South Plainfield, New Jersey. In the 1960's and 1970's, the company's business took on a more national scope. To handle this rapidly changing and expanding business, the company acquired the assets and customers of Promotional Packing Corporation of Los Angeles, California in 1974.

The company continued to expand its West Coast operations and in 1985 built a new manufacturing facility consisting of 70,000 square feet in Mira Loma, California. Other acquisitions throughout Ronpak's history included SAKS of Kansas City, Kansas, Sentinal Bag of Brooklyn, NY, and Salco Bag Company of Sidney, Florida. The acquisitions of these other companies have expanded the sales and manufacturing capabilities of Ronpak.