The size of physician networks can vary widely in plans purchased in the Affordable Care Act Marketplace.

One in five consumers with Marketplace plans reported that in the past year, a provider they needed was not covered by their insurance, according to the 2023 KFF Survey of Consumer Experiences with Health Insurance. Nearly 1 in 4 said a provider they needed to see who was covered by their insurance did not have appointments available.

"Enrollees with Marketplace coverage were more likely than those with employer coverage to face these challenges," KFF reported. "While the Centers for Medicare and Medicaid Services establishes minimum standards for the adequacy of provider networks for Marketplace plans, insurers retain considerable flexibility in how they design networks and how many providers they include. As a result, the breadth of plan networks varies considerably within counties, presenting challenges for consumers who need to select a plan with little information on the network breadth of their options."