Previous work by the RUPRI Center showed significant growth in hospital system membership among non-metropolitan hospitals from 2007 to 2012. Re-examining data from the American Hospital Association through 2016 shows continued growth in system membership among all categories of hospital size, location, and Critical Access Hospital (CAH) status. However, the growth rate in system membership declined in metropolitan hospitals in the South census region and non-metropolitan CAHs in all census regions. Our analysis also indicates that non-metropolitan CAHs and hospitals make up a small portion of hospitals in the largest healthcare systems. Non-metropolitan hospitals and non-metropolitan CAHs face unique challenges given the demographics of the population they serve, payer mix, and reimbursement levels.