New Primary Care Payment Mechanism Within Medicare Shared Savings Program Will Boost Role of Physician-Led ACOs, America’s Physician Groups Says

March 19, 2024

WASHINGTON, DC – The new Primary Care Flex model unveiled today by the Centers for Medicare & Medicaid Services (CMS) is a welcome addition that will boost the role of primary care in physician-led Medicare ACOs, America’s Physician Groups (APG) said today.

Under the model, some primary care physicians participating in the Medicare Shared Savings Program (MSSP) will be able to be paid differently than they typically are now, through the standard Medicare fee-for-service system. Instead, they could be eligible for partially capitated payments, as well as the opportunity to receive some of their shared savings prospectively, rather than after the end of a given performance year if the ACO has met savings targets. The new payment arrangement would be limited to so-called low revenue ACOs – a technical definition that means ACOs whose total revenue from Medicare Parts A and B is less than 35 percent of the A and B expenditures for the ACO’s assigned beneficiaries – which traditionally have been ACOs led by physicians.

“Experience shows that Medicare’s physician-led ACOs have produced superior results in terms of quality improvements and shared savings, and this new model could boost their performance further,” said Susan Dentzer, APG President and CEO. She noted that although Primary Care Flex will not enable participating clinicians to take on full risk for the costs and quality of care – unlike, for example, the ACO REACH Model – it is nonetheless a useful addition to the range of alternative payment models that are delivering positive results for patients and taxpayers. “In particular, getting some portion of shared savings in advance could help many physician practices make the needed investments in infrastructure and care redesign that are integral to advanced primary care,” Dentzer said.

CMS has said that the application process for Primary Care Flex will open this coming summer; that a limited number of applications will be approved; and that applicants must be participants in the MSSP to qualify. APG looks forward to garnering more details about the program and sharing them with its members.



About America’s Physician Groups
APG’s approximately 360 physician groups comprise 170,000 physicians, as well as thousands of other clinicians, providing care to nearly 90 million patients, including about 1 in 3 Medicare Advantage enrollees. APG’s motto, ‘Taking Responsibility for America’s Health,’ represents our members’ commitment to clinically integrated, coordinated, value-based health care in which physician groups are accountable for the costs and quality of patient care. Visit us at

Contact: Greg Phillips, APG Director of Communications, 202-770-1901