Understanding ACO Primary Care Flex Model
Beginning January 1, 2025, CMS launched the ACO Primary Care Flex (ACO PC Flex) model — a five-year initiative designed to strengthen primary care within the Medicare Shared Savings Program (MSSP).
This model represents a significant evolution in how primary care is financed and incentivized. It moves away from traditional fee-for-service (FFS) reimbursement toward a prospective, population-based payment system that rewards outcomes and equity. For physician-led and low-revenue ACOs, PC Flex could be a pivotal opportunity — here’s some key points to know.
Understand the Model’s Core Structure
At its heart, PC Flex replaces fee-for-service payments for many primary-care services with a monthly Prospective Primary Care Payment (PPCP).
Stable Revenue: CMS pays a fixed per-member-per-month (PMPM) amount to the ACO, based on a county-level rate adjusted for the population’s risk and demographics.
Advance Shared-Savings Payment: Participants receive an up-front payment to fund transformation efforts, technology, and staffing.
Eligibility: Only “low-revenue” ACOs — where A/B FFS revenue is under 35 % of total expenditures — may apply, and only ~130 ACOs are selected.
Duration: 2025–2029, with continued benchmarking and shared-savings/loss settlement through the MSSP.
For providers accustomed to visit-based billing, this is a paradigm shift: the focus moves from volume to value and care continuity.
Build Financial Readiness
Because the PPCP changes the cash-flow pattern, ACOs and affiliated practices should:
Model revenue impacts: compare historical FFS revenue versus expected PPCP inflows under different patient-mix and utilization assumptions.
Track fund allocation: CMS requires that at least 90 % of PPCP dollars (95 % in later years) be spent on “advanced primary-care” services.
Establish internal distribution rules: determine how the ACO will flow payments to participating providers and maintain transparency.
Strengthen reporting systems: quarterly attestations and spend-tracking are mandatory.
Tip: Work with actuaries or consultants to simulate both upside and downside risk scenarios so leadership fully understands margin sensitivity.
Redesign Care Delivery Around Proactive, Team-Based Care
PC Flex is intended to give practices flexibility to reimagine primary care.
Providers should:
Expand care-management and outreach programs to close gaps before acute events occur.
Invest in behavioral-health integration, telehealth, and home-based care — activities not always reimbursed under FFS.
Use the PPCP’s predictability to hire clinical extenders (RNs, pharmacists, social workers) who can support high-risk patients.
Leverage data analytics to identify chronic-disease cohorts needing proactive intervention.
This proactive orientation will also improve performance on MSSP quality measures and patient-experience scores — key drivers of shared savings.
Strengthen Risk-Adjustment and Documentation Accuracy
Although PC Flex alters payment mechanics, risk adjustment remains central to ACO benchmarking and performance.
Continue rigorous HCC coding and diagnosis capture at least annually for all beneficiaries.
Ensure your EHR problem lists are accurate, current, and linked to proper ICD-10 codes.
Deploy AI-driven risk-adjustment tools like ForeSee Medical to automate suspecting and documentation validation.
Train clinicians to code to the highest level of specificity — even when visit volume declines — since risk scores determine both PPCP adjustments and shared-savings benchmarks.
Remember: in a prospective model, missed diagnoses directly erode future-year revenue.
Invest in Data Integration and Reporting Infrastructure
CMS will expect participating ACOs to produce detailed reports on spending, care activities, and outcomes.
Preparation steps include:
Integrate disparate EHR data sources to capture full patient context.
Build dashboards that track PPCP utilization, attribution leakage, and performance metrics.
Implement FHIR-based interoperability tools to exchange information with partners, payers, and CMS in near real-time.
Use analytics to identify out-of-ACO primary care (PCOA) utilization that may affect benchmarks.
Cultivate Governance and Cultural Alignment
PC Flex success hinges on shared purpose between the ACO and its primary-care network.
Update governance charters to include PPCP fund management, compliance, and audit oversight.
Establish physician-led committees to monitor quality, documentation, and patient-equity outcomes.
Promote a culture of population-health accountability — aligning incentives so every provider understands how their actions affect the collective benchmark.
Key Takeaways for Providers
Opportunity: Predictable revenue, startup capital, and flexibility to innovate in care delivery.
Challenge: New accounting, reporting, and documentation discipline required.
Imperative: Maintain strong HCC risk-adjustment coding accuracy and diligence to protect future benchmarks.
Goal: Use prospective payments not to sustain status quo, but to transform primary care into a proactive, equitable, value-driven enterprise.
Final Thought
The ACO PC Flex model is CMS’s latest signal that primary care is the cornerstone of value-based transformation. For providers ready to lead, it’s a chance to modernize care delivery and capture sustainable revenue tied to real outcomes — not visit counts.
Those who prepare early, invest in documentation integrity, and harness AI-driven risk-adjustment technology will be best positioned to thrive in this next phase of Medicare’s evolution.
ForeSee Medical helps ACOs succeed under the ACO PC Flex model by ensuring accurate, compliant risk capture. Our AI-powered ForeSee ESP® platform automates diagnosis suspecting, coding validation, and documentation review—so providers can maintain precise risk scores and stable prospective payments. With ForeSee, organizations turn proactive primary care into measurable performance, compliance, and sustainable revenue.
Blog by: The ForeSee Medical Team