The Chehalis building was originally St. Helen Hospital. In 1907, the Dominican Sisters were asked to build a hospital in Chehalis. There was great rejoicing when the hospital opened in early December 1907. In 1927, a new brick St. Helen Hospital was built, featuring an elevator and more patient beds. In 1952, a new wing was added. In 1964, a nursing home (Rosary Manor) and another new wing was added. In 1966, the 1907 building was demolished. In 1969, a $1 million remodel took place. In July 1983, the Sisters of Providence assumed sponsorship of St. Helen Hospital.

Meanwhile, Centralia General Hospital, originally named Lewis County General Hospital, was built in 1926 through the efforts of six Centralia physicians who operated the hospital until 1937. The first facility, located on Iron Street, was three stories and contained 36 hospital beds.

In 1957 the Stewards Foundation, an organization of Evangelical churches, purchased the hospital for $100,000 and renamed it Centralia General Hospital.

As medical care and equipment became more sophisticated, the old facility on Iron Street became outdated, and in 1971 the Stewards Foundation built a new 47-bed facility at 1820 Cooks Hill Road. In 1979, a new wing was added for medical records, a business office, gift shop and classroom. In 1982, the ownership was transferred to Universal Health Services, Inc. With their help, the hospital was able to expand and purchase state-of-the-art equipment. The south wing of the hospital was added to include an intensive care unit.

In 1988, a union between the Sisters of Providence-owned St. Helen Hospital and Centralia General Hospital formed Providence Centralia Hospital.

In 1995, a new $14 million addition was added to the Centralia campus moving all patient care areas to this facility. A remodel of other patient areas was completed in 1996. The 1995-96 expansion and renovation of the Centralia campus added 66,000 square feet, a new emergency department, surgical services department, outpatient surgery center, diagnostic imaging and 60-bed medical floor, including critical care.