CareSource is a nonprofit that began as a managed health care plan serving Medicaid members in Ohio. Today, it provides public health care programs including Medicaid, Medicare, and Marketplace. The company is headquartered in Dayton, Ohio. It is the largest Medicaid plan in Ohio and second largest in the United States.
The 313 area code is registered in Michigan. 87.57% of phone numbers within the 313 area code are registered as residential/consumer phone numbers, and 12.43% are registered as commercial/business phone numbers.
The National Plan Area (NPA) 313 was created in 1947 as one of the original 86 codes. Originally, it included the entire southeastern quadrant of Michigan, including Metro Detroit, Flint, and the southern part of Michigan's  Thumb ..n December 13, 1997, the 313 area was further divided, creating the 734 area out of Washtenaw County, Monroe County, and western and Downriver Wayne County. Area code 679 has been reserved as a future overlay to the 313 area.