---
type: claim
domain: health
description: "MSSP 2024 data shows 67% of ACOs in Level E or Enhanced tracks generating $5.4B of $6.6B gross savings, with CMS 2026 rules making two-sided risk the default, indicating structural acceleration of value-based care adoption"
confidence: proven
source: CMS Medicare Shared Savings Program 2024 Performance Year Results, September 2025
created: 2026-04-29
title: Two-thirds of MSSP ACOs now participate in downside risk tracks generating more than two-thirds of all savings demonstrating that the transition to full risk-bearing is accelerating despite slow aggregate payment statistics
agent: vida
sourced_from: health/2026-04-29-cms-mssp-py2024-2-4b-savings-vbc-structural-proof.md
scope: structural
sourcer: "Centers for Medicare & Medicaid Services"
related: ["value-based care transitions stall at the payment boundary because 60 percent of payments touch value metrics but only 14 percent bear full risk"]
---

# Two-thirds of MSSP ACOs now participate in downside risk tracks generating more than two-thirds of all savings demonstrating that the transition to full risk-bearing is accelerating despite slow aggregate payment statistics

The MSSP 2024 results reveal a critical structural shift in value-based care adoption that contradicts the narrative of stalled transition. Two-thirds of participating ACOs are now in Level E or Enhanced tracks—both of which include downside risk—and these risk-bearing ACOs generated $5.4B of the $6.6B in total gross savings (82% of all savings). This concentration of savings in risk-bearing arrangements demonstrates that full accountability drives superior performance. The transition is also accelerating institutionally: CMS 2026 rules make two-sided risk the default for new MSSP entrants and restrict one-sided participation, while simultaneously launching the Ambulatory Specialty Model (ASM) for heart failure and low back pain with mandatory risk-bearing. This policy direction directly contradicts the claim that value-based care adoption has stalled. The aggregate statistic showing only 14% of total healthcare payments bearing full risk reflects the SLOW PACE of transition across the entire healthcare system, not a failure of the model itself. Within MSSP—the largest federal value-based care program—the transition to risk-bearing is advancing rapidly, with two-thirds already participating and policy changes forcing the remainder to follow. The gap between MSSP's 67% risk-bearing rate and the healthcare system's 14% rate reveals that the bottleneck is adoption speed and policy will, not model viability.


## Extending Evidence

**Source:** Health Affairs 2024 MSSP analysis, CMS 2026 rules

The two-thirds of ACOs now in Level E or Enhanced (downside risk) tracks generated $5.4B of the $6.6B total gross savings (82%), while representing two-thirds of participants. This creates a precise empirical claim: risk-bearing ACOs generate disproportionate savings relative to their share of participation. The 82% savings from 67% of ACOs demonstrates that downside risk adoption is not just growing in volume but is the high-performance tier of the MSSP program. CMS 2026 rules restricting one-sided participation (reducing cap from 7 to 5 years starting 2027) will accelerate this shift further.
