12.1 Group Health Fundamentals and Eligibility

How Group Health Coverage Is Structured

Group health insurance covers a defined group of people under a single contract rather than issuing a separate policy to each insured. The insurer issues one master policy (master contract) to the policyowner, who is almost always the employer or a sponsoring organization. Individual members do not own a policy. Instead, each covered employee receives a certificate of insurance that summarizes benefits, exclusions, and conversion rights. On the exam, remember the relationship: the group is the policyowner; the individual holds a certificate, not a contract.

This design lowers cost two ways. First, marketing and administration are spread across many lives at once. Second, the group itself reduces adverse selection, the tendency of less-healthy people to seek coverage. Because employees join for employment reasons rather than because they expect to file claims, the risk pool stays balanced.

Group Eligibility Requirements

To qualify as an insurable group and prevent adverse selection, four rules are tested repeatedly:

• Existence for another purpose — the group must be formed for a reason other than obtaining insurance (e.g., to run a business or a labor union).
• Flow of membership — new members must steadily join and old ones leave, keeping the risk pool fresh.
• Defined eligibility classes — benefits are based on objective conditions (full-time status, job class, length of service), never on individual health.
• Minimum participation — enough of the group must enroll so the risk stays spread.

An actively-at-work clause states that coverage takes effect only if the employee is actively performing job duties on the effective date; if home sick that day, coverage starts when the employee returns. This blocks last-minute enrollment of a worker already too ill to work.

Enrollment Periods

Eligible employees enroll during the initial enrollment period when first eligible. After that, they generally must wait for the open enrollment period (typically annual). A special enrollment period (SEP) is triggered by qualifying life events such as marriage, birth or adoption, divorce, or loss of other coverage, and usually lasts 30 days. An employee who declines during initial enrollment and tries to join later outside an SEP is a late enrollee and historically faced delays or evidence of insurability.

The Actively-at-Work Trap

Exam questions love the timing of the actively-at-work provision. Consider an employee whose coverage is scheduled to begin Monday. He is hospitalized Sunday and is not at work Monday. Because he was not actively at work on the effective date, his coverage does not begin until he returns to active duty. This is not a denial based on health underwriting; it is a contractual condition precedent that applies uniformly to all new entrants and protects the pool from enrolling lives already in claim status.

A related distinction often confused on exams:

• Probationary period — the time a new employee must wait before becoming eligible to enroll (capped at 90 days under the ACA).
• Elimination period — in disability coverage, the waiting time after a disability begins before benefits are paid. These are unrelated; do not swap them.

Dependent and Continuation Basics

Group plans typically extend coverage to a spouse and eligible dependent children. Under the ACA, plans offering dependent coverage must allow children to remain until age 26, regardless of student or marital status. When employment ends, federal COBRA and state mini-COBRA laws let qualified beneficiaries continue coverage temporarily (covered in 12.3). A conversion privilege may also let a departing insured convert to an individual policy without proving insurability, though premiums rise to individual rates.

Coordination of Benefits (COB)

When a person is covered under more than one group plan, the coordination of benefits provision prevents collecting more than 100% of the actual expense. One plan is primary (pays first up to its limits) and the other is secondary (pays the remaining allowable expense). The widely tested birthday rule decides which parent's plan is primary for a dependent child: the plan of the parent whose birthday falls earlier in the calendar year (month and day, not year of birth) is primary.

Worked Example — COB With the Birthday Rule

A child is covered under both parents' group plans. The mother's birthday is March 10; the father's is August 22. The mother's plan is primary because March precedes August. Suppose a covered claim is $2,000. The mother's plan (primary) pays its share of $1,400. The father's plan (secondary) then pays up to the remaining allowable expense, $2,000 - $1,400 = $600, so the family pays nothing and total payment never exceeds the $2,000 expense. Without COB, the family could otherwise collect $1,400 + a separate benefit and profit from a loss, which COB forbids.

For the employee themselves, the plan where the person is an active employee is primary over a plan where they are covered as a dependent. Coordination keeps group coverage an indemnity against loss, not a source of gain, and is a frequent exam item paired with the birthday rule.