As of January 2026, 14.3 million Medicare beneficiaries receive care
through ACOs, and the financial pressure on those arrangements has grown
steadily. Shared savings models reward ACOs that keep the total cost of care in
check. Those who don't absorb the difference. The organizations pulling ahead
aren't necessarily the largest or best-resourced. They're the ones that know
where their spending is concentrated and have the infrastructure to act on it
before reconciliation surfaces the damage.
Here are the major ACO Cost Drivers
where most of that spending originates, and what
controlling it actually requires.
Preventable Hospitalizations and Readmissions
Avoidable inpatient admissions sit at the top of the cost list for most
attributed populations. Chronic disease patients who slip through without
follow-up, medication checks, or any clinical touchpoint between visits tend to
end up back in the hospital. Each readmission chips away at shared savings that
took the rest of the year to build.
Getting ahead of this requires visibility before the admission, not
after. ADT feeds, lab trends, and pharmacy fill data need to reach a risk model
that puts the right patients in front of a care manager, while a phone call can
still change the outcome. Once a patient is back in the ED, the cost has
already happened.
The 7-day and 30-day post-discharge windows carry the highest
readmission risk. ACOs that track those windows actively and follow up
consistently see lower rates. Those that don't, don't.
Care Management Program Efficiency
Care management costs, including coordinators, patient education, and
high-risk monitoring, represent ongoing operational expenses that need to
generate measurable savings to justify.
Running the same care management intensity across every attributed
patient burns coordinator time on patients who don't need it, and leaves
high-risk patients with less attention than their clinical situation warrants.
Sorting patients accurately by risk level is what makes the math work:
high-risk patients get active management, rising-risk patients get monitoring
and outreach, and stable patients stay on routine preventive schedules.
Health IT Infrastructure as a Cost Driver
ACOs running on disconnected systems don't find out where their cost
problems are until claims settle, which is weeks or months after any practical
window to respond. Manual reconciliation slows everything down: risk
identification, leakage monitoring, and utilization tracking all lag behind the
actual clinical picture. By the time the data is clean enough to act on, the
performance period has moved on.
A platform that pulls from EHRs, claims, labs, pharmacy, and ADT feeds
gives ACOs the visibility to manage ACO Cost Drivers before they show up
at year-end reconciliation. For most ACOs, particularly those managing fewer
than 50,000 covered lives, an established population health platform delivers a
better return than attempting to piece together custom systems.
Provider Alignment and Compensation Models
Provider compensation models that reward volume give physicians no
practical reason to reduce unnecessary referrals, limit high-cost imaging, or
coordinate post-discharge care closely. Physicians working under traditional
fee-for-service arrangements are financially indifferent to the cost outcomes
the ACO is responsible for.
ACOs that connect physician compensation to quality performance,
utilization targets, and shared savings results give their networks a reason to
work differently. That alignment takes time to build, but without it, clinical
programs the ACO invests in will always compete against incentives pulling in
the opposite direction.
Getting Control of What's Driving Cost
Managing ACO Cost Drivers isn't a one-time project. It requires
continuous data, connected workflows, and the ability to track utilization,
risk, and quality trends across the full attributed population in real time.
Persivia solution gives ACOs the infrastructure to do exactly that. It aggregates data from over 70 EHR and practice management systems, runs AI-driven risk stratification that updates as new data arrives, monitors post-acute utilization and leakage across every connected care setting, and surfaces HCC coding gaps at the point of care. For ACOs managing complex Medicare populations under tight benchmarks, that level of visibility is what turns cost driver awareness into actual shared savings performance.




