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HSO’s Company History: Past and Present

It all started with a five-gallon can. On February 12, 1930, HSO was born when Ted Kohler first started supplying coal, stove oil, and kerosene for customers’ homes and farms. After 23 years of business, Elmer and Lillian Mangelsdorf acquired HSO. The company grew well into the 70s with the creation of the I-55 Motor Plaza and Mango Distributing. Sadly, Elmer passed in 1985 and Lillian ran the business with her son David, President, and her daughter Sandra, Secretary/Treasurer.

The next two decades saw an aggressive expansion of our convenience stores, including Express Mart, and HSO began to service the entire eastern quadrant of Missouri from St. Charles to West Plains, to the Mississippi River. David’s son, Zachary, joined the family business in 2016 as Sales Manager and hired a sales force and support staff. Two years later, David promoted Zachary to President, making him the third generation of Mangelsdorfs to be President of HSO.

Today, there are 160 employees, nine convenience stores, one truck stop, and around 70 wholesale dealer accounts. HSO delivers gasoline and diesel fuels to farms, homes, construction sites, and commercial accounts. We also supply VP Racing Fuels and jet fuel.

HSO runs four tank trucks, one oil tank truck, and three box delivery trucks. We also have seven transport trucks across both of our divisions in Poplar Bluff and Barnhart, MO. Express Mart currently has nine locations across Jefferson and Washington County.

Over the last 90 years, our industry has continued to change, but we are evolving every day with those changes. HSO believes that we must consistently provide our customers with quality products at competitive prices to fit their needs. Honesty and integrity are our top priorities in carrying out superior service to our customers.

“Service” will always be our middle name. Contact us today at 1-800-467-5044 to find out more or to request our services.




6910 Front Street. Barnhart, Missouri 63012

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Mailing Address

PO Box 9 Barnhart, Missouri 63012