6.1 Group Health Underwriting

Characteristics of Group Health Insurance

Group health insurance is a single master contract (also called a "group contract") issued to the policyholder — typically the employer — that covers a defined group of eligible employees and their dependents. The employer is the contract holder; employees receive a certificate of coverage (evidence of insurance) summarizing benefits, but they are not parties to the master contract. This distinction matters for legal standing: employees cannot unilaterally modify the contract, and disputes are handled through the plan's appeals process and ERISA remedies (where applicable) rather than individual policy negotiations.

Key characteristics that distinguish group health from individual health insurance:

• Single contract covers many lives — administrative economy of scale lowers per-life cost.
• Master contract / certificate structure — employer holds the contract; employees hold certificates.
• Sponsorship — the employer (or employee organization) sponsors the plan; individuals cannot form a group solely to buy insurance (except through legitimate association plans meeting state requirements).
• Eligibility tied to employment status — coverage generally ends when employment ends (subject to COBRA continuation).
• Guaranteed issue within eligibility — no individual medical underwriting in the group; eligibility turns on employment status and plan waiting periods, not health status.

Eligibility and Waiting Periods

To enroll, an employee must satisfy the plan's eligibility requirements, which typically include:

1. Active, full-time employment — commonly defined as 30+ hours/week (tied to ACA's 30-hour full-time definition for applicable large employers). Part-time employees may be excluded or offered separate pro-rated coverage.
2. Completed waiting period — the time between hire date and the first day coverage can begin. Under ACA §2708, waiting periods cannot exceed 90 days (calendar days from the date the employee would otherwise be eligible). States may impose shorter limits; no state may extend the federal cap.
3. Dependent eligibility — spouses and children up to age 26 (the ACA dependent coverage mandate) qualify; stepchildren and adopted children are included on the same terms as biological children.

New hires who decline coverage at initial eligibility can typically enroll later only at the plan's open enrollment period or upon a special enrollment event (marriage, birth/adoption, loss of other coverage, or certain HIPAA special enrollment triggers).

Group Underwriting: No Individual Medical UW

Unlike individual insurance, group health underwriting focuses on the group as a whole, not the health of any one member. The insurer prices the group based on:

• Census data — age, sex, geography, family composition, occupation/industry classification.
• Industry and SIC/NAICS code — hazardous occupations (construction, mining, logging) may carry higher rates; white-collar groups typically receive lower rates.
• Contribution level — the share the employer pays influences participation (see §6.2) and thereby adverse selection.
• Prior claims experience — for experience-rated groups (typically 50+ employees), the insurer reviews past claims to set the renewal rate; for smaller groups, community rating applies under ACA rules (no health-factor rating; only age, tobacco, geography, and family size may vary premium).

The critical principle: no individual medical underwriting. An employee with diabetes, cancer, or prior surgery cannot be singled out for denial or higher rates within the group. This is why group coverage has historically been the primary route to coverage for people with pre-existing conditions — a role now reinforced by the ACA's guaranteed issue in the individual market as well.

Minimum Participation Requirements

Insurers require a minimum percentage of eligible employees to enroll, to prevent adverse selection — the scenario where only the sick sign up. The conventional industry standard is 75% of eligible employees must participate when the plan is contributory. Noncontributory plans (employer pays 100%) typically have no participation requirement because there is no economic reason for an eligible employee to refuse "free" coverage.

If the group fails the participation test, the insurer may decline to issue, rescind the offer, or require the employer to raise its contribution level to push participation above the threshold. Some carriers apply a relaxed test (e.g., 65%) for small groups, but 75% remains the textbook benchmark for the A&H exam.

Employer Sponsorship and the Group Concept

The group insurance model rests on the employer as a sponsor: the employer selects the plan, remits premiums (often through payroll deduction), and serves as the communication channel to employees. This sponsorship is what makes the group economically viable — without employer aggregation, the marketing and administrative cost per life would rival individual insurance.

For association and trust arrangements (e.g., trade associations, multiemployer Taft-Hartley trusts), the sponsoring organization plays the same role as the employer. Legitimate group plans require a genuine commonality of interest — an ad hoc group formed solely to buy insurance is not a valid group and is prohibited in most states as a subversion of individual underwriting rules.

Adverse Selection in the Group Context

Adverse selection is the central economic risk group underwriting controls. By requiring minimum participation and employer contribution, the insurer ensures the group includes a representative mix of healthy and less-healthy lives. The 75% threshold for contributory plans is calibrated so the risk pool stays balanced; if only the 25% with chronic conditions enrolled, claims would exceed premiums and the plan would be unsustainable.

This is also why late enrollees who declined initial coverage are typically required to wait for special enrollment or open enrollment — to prevent people from joining only when they need care. The interplay between participation rules, contribution levels, and adverse selection is the engine that makes employer-sponsored coverage work.