PAC Announces New Collaboration with Astrana Health for Independent Primary Care Physicians
Frequently Asked Questions
PAC and Astrana Health are collaborating to give PAC-affiliated primary care physicians priority access to Astrana’s Accountable Care Organization (ACO) programs. Through this collaboration, PAC providers can participate in value-based care arrangements — including the Medicare Shared Savings Program (MSSP) and the upcoming LEAD (Long-Term Enhanced ACO Design) model — without giving up practice independence or ownership.
Astrana serves as the ACO enabler: handling financial projections and analysis, contracting, clinical support, care management, and shared savings distribution. PAC’s role is to introduce and guide affiliated physicians through the evaluation and enrollment process.
Astrana Health (NASDAQ: ASTH) is one of the nation’s largest physician-led, value-based care organizations. Founded in 1992 as Allied Physicians of California (APC), the company has grown over the last 34 years into a nationally integrated platform operating across 16+ states, with 20,000+ providers in network, 1.6 million+ lives under management, and $3.18 billion in 2025 revenue.
Astrana operates three business segments: Care Partners (affiliated provider network), Care Delivery (owned primary care and multi-specialty clinics, labs, Skilled Nursing Facilities, and a hospital), and Care Enablement (full-stack technology and solutions platform). The company has a 98% annual provider retention rate and an average provider tenure of 11.1 years — a reflection of consistent delivery on its financial and operational commitments.
An Accountable Care Organization (ACO) is a voluntary network of healthcare providers — doctors, hospitals, and other clinicians — who coordinate care for a defined patient population and share financial accountability for outcomes.
In the Medicare context, ACOs enter an arrangement with CMS where, if they keep the total cost of care for their attributed beneficiaries below a risk-adjusted benchmark while meeting quality standards, they earn a portion of those savings — called Shared Savings. Astrana absorbs all downside financial risk on behalf of participating providers, meaning practices have access to the upside without practice-level financial exposure. Think of it as physicians “linking arms” to gain scale and resources while remaining fully independent.
For providers: Participating physicians receive guaranteed monthly incentive payments above their traditional fee-for-service (FFS) reimbursement — typically the equivalent of $10–$12 per member per month (PMPM) — paid throughout the year regardless of ACO performance. Back-end shared savings are also available based on individual practice and ACO-wide performance. In 2024, the average Astrana ACO provider earned $375+ per member per year (PMPY), with top performers exceeding $700 PMPY. On a member-weighted average basis, providers supplemented their FFS income by 59%.
Providers also receive risk adjustment coding support, quality measure education, care management staffing extension, and data dashboard tools — all without imposing new workflows or requiring changes to practice ownership.
For patients: Astrana wraps clinical support programs around ACO-attributed Medicare beneficiaries. This includes post-discharge outreach (Transitions of Care), care management for complex or high-utilization patients, disease management programs for conditions like CHF, COPD, and ESRD, and Annual Wellness Visit support. Patients receive more coordinated, proactive care — especially those managing multiple chronic conditions.
Medicare ACOs operate within Traditional (Original) Medicare — they are not a Medicare Advantage product. Beneficiaries keep their full freedom to see any Medicare provider and retain all standard Medicare benefits. Providers continue to bill and collect under FFS; the ACO layer sits on top, allowing participating practices to also earn shared savings. You may occasionally hear about commercial ACOs as well – these are distinct and separate from Medicare ACOs. PAC’s partnership with Astrana is through Astrana’s Medicare ACOs.
Traditional Medicare: ACOs operate here. Beneficiaries are “attributed” to an ACO based on their primary care utilization history — no enrollment or action required by the patient. This “attribution” creates a relationship between the ACO and the attributed beneficiaries where the ACO is financially accountable for their total cost of care, but the beneficiary may continue to see any provider that accepts Medicare, whether they are in an ACO or not.
Medicare Advantage (MA): A private insurance product with capitated payments and network restrictions. ACO participation is separate from and does not conflict with MA contracts.
Commercial/Medicaid: Astrana’s ACO programs are Medicare-specific (MSSP and REACH/LEAD). Commercial and Medicaid value-based arrangements exist separately and are not part of this program.
CMS has committed to having 100% of Medicare beneficiaries in accountable care relationships by 2030, making ACO participation increasingly central to any independent practice’s long-term strategy.
Astrana currently operates four ACO entities for PY2026: three MSSP ACOs and one REACH ACO (Realizing Equity, Access, and Community Health model).
The Medicare Shared Savings Program (MSSP) is the flagship CMS program for ACOs, codified into law by Congress in 2012. Providers share in savings generated when total cost of care for the ACO’s attributed beneficiaries falls below a risk-adjusted benchmark while meeting quality thresholds. Astrana has achieved 12 consecutive years of positive shared savings and had one of its MSSP ACOs rank 8th out of 476 MSSP ACOs nationally in PMPM savings in 2024.
ACO REACH is a CMS Innovation Center model with enhanced risk-sharing mechanics. It is currently active through the end of 2026, when it will transition to the LEAD model beginning in 2027.
Astrana’s actuarial team conducts a custom financial analysis for each prospective practice to recommend the optimal program based on their patient population, risk profile, and benchmark dynamics. The financial model is program-agnostic — guaranteed incentives and the opportunity for back-end shared savings are structured consistently across both options.
The most significant change for 2027 is the launch of the LEAD model (Long-Term Enhanced ACO Design) by the CMS Innovation Center. LEAD replaces the ACO REACH program and begins January 1, 2027, with a 10-year performance period running through 2036.
LEAD is designed to provide practices with a longer-horizon commitment, with greater stability and predictability in their value-based care strategy. CMS has structured the model to increase focus on high-needs patient populations and care coordination across complex cases. Astrana is positioned for nationwide LEAD participation due to our participation in ACO REACH.
The MSSP program continues alongside LEAD for 2027. Practices evaluating PY2027 participation will work with Astrana’s actuarial team to determine which model is the better fit.
For practices entering the LEAD model, the 10-year horizon creates a longer runway for shared savings accumulation. Practices with opportunity to reduce unnecessary utilization — particularly around SNF stays, ED visits, and readmissions — stand to benefit significantly over time as their performance relative to the benchmark improves.
From an operational standpoint, the transition from REACH to LEAD is designed to be seamless for practices already working with an ACO enabler like Astrana. Care management programs, quality support, and provider portal tools remain consistent from REACH into LEAD, and for MSSP as well.
The primary practical consideration for 2027 is timing. Practices must withdraw from any conflicting ACO agreements and submit their final provider roster to Astrana by late July 2026. Practices that miss this window cannot participate in either MSSP or LEAD until 2028. With LEAD’s launch and CMS’s stated goal to have 100% of Medicare beneficiaries in an accountable care relationship, this is one of the most consequential enrollment cycles for independent practices in a decade.
Practices evaluating ACO participation for 2027 should consider the following:
Program Fit & Financial Projections: MSSP or LEAD — recommendations based on your patient mix, risk profile, and current TIN-level performance. Astrana provides a complimentary actuarial analysis and custom proforma for every group going through due diligence. The analysis includes projected guaranteed incentives, estimated back-end savings, and how your net reimbursement compares against FFS-only — using CMS data so you have a clear, numbers-driven picture.
Existing ACO Relationships: Already in another ACO? Not a problem – practices have time to weigh their options and choose the best partner heading into 2027, having to commit by CMS deadline of August 3rd 2026 for 2027.
Operational Compatibility: Astrana’s programs are built to work alongside your existing workflows, not overhaul them. We’re EHR agnostic — able to support the majority of systems already in use. For practices that need a new EHR solution, we also offer access to Elation at a preferred rate.
Deadline Awareness: The deadline for provider roster submission is late July 2026, which means analysis and contracting should kick off no later than June.
Interested providers or practice administrators should reach out directly to Astrana’s ACO Growth team. The primary contact for this collaboration is:
Sean Zargari
Senior Director, ACO Growth
Cell: (407) 902-8887
Email: sean.zargari@astranahealth.com
Web: https://www.astranahealth.com/become-an-astrana-aco-partner-pac-referral/