A large group health plan is employer-sponsored health insurance offered by a company with 50 or more full-time employees. These plans operate under different rules than insurance sold to individuals or small businesses, with distinct pricing methods, regulatory requirements, and benefit structures that affect both what you pay and what your coverage includes.
How “Large Group” Is Defined
The threshold that matters most under federal law is 50 full-time employees. The IRS counts anyone working at least 30 hours per week (or 130 hours per month) as full-time. Part-time workers also factor in: their combined hours are converted into “full-time equivalents” and added to the total. To calculate workforce size, an employer adds its full-time employees and full-time equivalents for each month of the prior calendar year, then divides by 12.
If that average hits 50, the employer becomes what the IRS calls an “applicable large employer,” or ALE. This designation triggers a set of legal obligations that smaller companies don’t face.
It’s worth noting that some states draw the line differently for insurance regulation purposes, using 100 employees rather than 50 to separate the small group market from the large group market. The 50-employee threshold is the federal standard under the Affordable Care Act.
What Large Employers Are Required to Offer
Large employers don’t get a choice about whether to offer health coverage. Under the ACA’s employer shared responsibility provisions, an ALE must offer minimum essential coverage to at least 95 percent of its full-time employees and their dependents. The coverage must meet two standards: it has to provide “minimum value,” meaning the plan pays at least 60 percent of expected health care costs for a standard population, and it must be “affordable,” meaning the employee’s share of the premium stays below a set percentage of their household income (9.96 percent for plan years beginning in 2026).
Employers that fail to offer qualifying coverage face financial penalties, but only if at least one full-time employee ends up getting a premium tax credit to buy insurance through the ACA marketplace instead. The penalty for not offering coverage at all is $2,970 per full-time employee per year (the 2024 figure), minus the first 30 employees. An employer that offers coverage but has it fall short on affordability or minimum value pays $4,460 per year for each employee who receives a marketplace tax credit.
How Pricing Differs From Small Group Plans
This is one of the biggest practical differences between large and small group insurance. Small group plans use community rating, where an insurance carrier charges the same premiums to all companies in a geographic area regardless of their employees’ health history, gender, or how much care they’ve used. Everyone in the same region on the same plan pays the same rate.
Large group plans work the opposite way. Insurers evaluate your specific company’s demographics, workforce age, and past claims history to set your premium. This is called experience rating. If your workforce is younger and healthier than average, your company may pay less than it would on a community-rated plan. If your group has had expensive claims, premiums may be higher. These rates are typically reassessed at each annual renewal, taking both company-specific data and broader market trends into account.
Benefits and Coverage Rules
The ACA requires individual and small group plans to cover ten categories of essential health benefits: ambulatory care, emergency services, hospitalization, maternity and newborn care, mental health and substance use services, prescription drugs, rehabilitative services, lab work, preventive care, and pediatric services including dental and vision. Large group plans are not held to that same essential health benefits requirement. In practice, most large employers offer robust benefit packages that cover these categories anyway, since they’re competing for talent. But they have more flexibility to design their plans, potentially excluding or limiting certain benefits that small group plans must include.
All non-grandfathered plans, including large group plans, still must cover preventive services with no cost-sharing and cannot impose annual or lifetime dollar limits on essential health benefits. They also cannot deny coverage or charge more based on preexisting conditions.
Self-Insured vs. Fully Insured Plans
Large employers frequently choose to self-insure, meaning the company pays employee health claims directly out of its own funds rather than purchasing a policy from an insurance carrier. The employer typically hires an insurance company or third-party administrator to process claims and manage the plan, but the financial risk stays with the employer.
This distinction matters because self-insured plans are regulated by a federal law called ERISA, which preempts most state insurance laws. That means state-level protections you might expect to have, like coverage mandates for fertility preservation (required in 21 states and Washington, D.C.), extended dependent coverage beyond federal rules, or standardized prior authorization processes, often don’t apply to self-insured plans. In California, for example, a state continuation coverage law that extends benefits beyond federal COBRA only applies to fully insured plans. If your large employer self-insures, your coverage is governed almost entirely by federal rules rather than whatever your state requires of insurance companies.
How Large Group Plans Interact With Medicare
If you’re 65 or older and still working at a company with 20 or more employees, your employer’s group health plan pays first and Medicare pays second. This “Medicare Secondary Payer” rule means your employer plan is your primary insurance, and Medicare only picks up costs that the group plan doesn’t cover. The 20-employee threshold is met when a company has 20 or more full-time or part-time employees on each working day in at least 20 calendar weeks of the current or prior year.
If you work for a smaller employer with fewer than 20 employees, the situation reverses: Medicare becomes your primary payer and the employer plan is secondary. This distinction directly affects how your claims are processed and what you owe out of pocket, so it’s worth confirming your employer’s size if you’re Medicare-eligible and still on a group plan.
Reporting Requirements for Large Employers
Large employers have annual reporting obligations to the IRS that prove they’re offering the required coverage. They file two forms: Form 1094-C, which summarizes company-wide coverage information, and Form 1095-C, which reports coverage details for each individual employee. Employees receive a copy of their 1095-C, which they may need when filing taxes to verify they had qualifying health coverage.
For the 2025 calendar year, employers must furnish Form 1095-C to employees by March 2, 2026. The IRS filing deadline is March 2, 2026 for paper filers and March 31, 2026 for electronic filers. If you’re a full-time employee at a large company and don’t receive this form, it’s worth following up with your HR department, since it documents your coverage status for the year.