Accountable Care Organization (ACO)
An Accountable Care Organization (ACO) is a group of doctors, hospitals, and other providers that share accountability for the cost and quality of care for a defined patient population.
Updated
An Accountable Care Organization (ACO) is a care-delivery and payment model in which a group of providers — typically physicians, hospitals, and other suppliers — voluntarily form an organization that is held accountable for the overall cost and quality of care delivered to a defined group of patients. ACOs are most established in Medicare (the Shared Savings Program and successor models), but commercial and Medicaid ACOs also exist.
The model ties payment to performance against cost and quality benchmarks rather than paying purely per service. When an ACO meets its quality and cost targets it may share in the savings it generates; depending on the track, it may also share in losses, which is what makes the accountability real rather than nominal.
In practice
For a billing operation, ACO participation changes the downstream conversation about utilization and documentation rather than the front-end claim itself — claims are still submitted to the same payer. The downstream risk is that under-documentation or over-utilization affects the ACO's cost performance and therefore shared savings or losses, so coding specificity and medical-necessity support matter beyond whether an individual claim is paid.
Commonly confused with
- Bundled payment: A bundled payment pays a single amount for an episode of care; an ACO holds a group accountable for total cost and quality across a population over a period. The two are alternative value-based payment shapes.
- Value-based care: Value-based care is the broad category of paying for value over volume; the ACO is one specific model within it.