Premera Blue Cross operates on the Blue Cross Blue Shield's health insurance license on not-for-profit basis. It was formed through the merger of Blue Cross of Washington with Spokane's Medical Service Corporation in June, 1998. Its headquarters are based in Washington's, Mountlake Terrace. Premera's history dates back to 5th May, 1945 when it was established as Washington Hospital Service. It began its operations in Alaska during 1957. Washington Hospital Service was renamed to Blue Cross of Washington on 14th March 1969.
Premera offers its health plans under the license of Blue Cross in whole Washington apart from Clark County and also offers health plans in Alaska license of Blue Cross and Blue Shield. It also has some sub-brand like Lifewise which offers health insurance in Arizona, Oregon & Washington and Calypso which assists the health insurers in prevention as well as recovery of the provider overpayments.