St. Tammany Parish Hospital Service District No. 1 opened its doors Dec. 1, 1954, after an eight-year project that began in 1946 with the Women's Progressive Union of Covington speaking to churches, missionary circles, home economics groups, farmers and sewing circles.

In May 1951, under the federal Hill-Burton Law and Title VI of the Public Health Service Act, the St. Tammany Parish Police Jury voted a bond issue of $175,000 coupled with $240,000 in federal funding. This humble beginning shows a rare time in its history when St. Tammany Parish Hospital relied upon tax funding. Today’s STHS receives no ad valorem tax funding, relying entirely upon its own operations, investments and the generous donors to the St. Tammany Hospital Foundation.

May 4, 1953, members of St. Tammany Parish Hospital Board of Commissioners participated in a ground-breaking ceremony for the $365,000 hospital. This would mark the first of many groundbreaking ceremonies over the next five decades, each successive project adding new capabilities and capacity to the growing hospital.

The original building was nearly complete in 1954 when officials recognized the need for an operating capital drive to enable the new venture time to become self-sufficient. Again the generous people of Covington showed their support, raising funds and donating items to furnish several private rooms, the nursery, the pediatrics ward, operating rooms, and even landscaping for the grounds.

The hospital opened as a 15-bed general hospital. Its first expansion was a 15-bed west wing, added in 1958. A 61-bed addition was constructed in 1966, and in 1974, a new wing including obstetrics was added. Expansions have continued with each decade, with the largest single expansion, dubbed the Millennium Project, tripling the size of the hospital, 1996-2003. It was a 203-bed hospital until the 2008 addition, which brought it to 223. The 2013-16 expansion brought the number of beds to 232. A 2018-2020 expansion plan will transition the hospital to all private rooms and increase critical care capacity.

Today, St. Tammany Health System is the largest hospital in the parish, serving the needs of its patients throughout the region with the latest technology and caring touches, delivering on the promise of world-class healthcare close to home. Current expansion plans include inpatient and outpatient services designed to ensure the hospital's ability to meet its mission into the future.