When a patient is covered under two group plans, which plan is considered primary?

In situations where a patient is covered under two group health insurance plans, determining which plan is considered primary is guided by specific coordination of benefits rules. The primary plan is responsible for paying first when a claim is submitted.

The most widely used rule to establish primary coverage is based on the duration of the coverage: the plan that has been in effect for the longest period of time is deemed the primary plan. This approach prioritizes continuity and stability in coverage, as the longer a plan has been active, the more established it typically is in its terms and benefits.

Choosing the plan based on the lowest premium, the most recently acquired plan, or the plan offering more extensive coverage does not align with the standard practices for coordination of benefits. These factors do not reflect the underlying principles designed to streamline payment responsibilities between multiple insurers. Instead, the length of time a plan has been in force serves a clear and logical rationale for determining which plan takes precedence in paying for healthcare expenses.