Pooling risks from across a certain population can minimize premium variances between groups and premium fluctuations per group. A reinsurance pool covers the excess costs associated with high-risk insureds from numerous employer groups. A high-risk insured is one who is likely to generate substantial claims.

Pooling and reinsuring risks helps keep underlying plan premiums more predictable and therefore lower. The excess costs are shared proportionately among all pool members (reinsurers). As a result, a pool helps make insurance coverage more affordable and available and encourages insurers to continue offering coverage to otherwise uninsurable groups.