Open Enrollment begins Nov. 1 OKLAHOMA CITY, Oct. 2, 2024 /PRNewswire/ -- Ambetter of Oklahoma, a product offered by a Centene Corporation (NYSE: CNC) company which provides insurance to under-insured and uninsured populations through the federal Health Insurance Marketplace®, announced today it will reduce plan premiums to residents in 36 counties in Oklahoma for 2025. Open enrollment for the Health Insurance Marketplace for Oklahoma runs from Nov. 1, 2024, through Jan. 15, 2025. Enroll by Dec. 15, 2024, f ...