Medicare 2026

Working for a Small Employer at 65? Here's Why Medicare Usually Pays First

If you're approaching 65 and still working — or your spouse is — the size of the employer matters more than most people realize. Under federal "Medicare Secondary Payer" rules, the number of people working at the company determines whether your job-based plan pays your medical bills first or whether Medicare does. If the employer has fewer than 20 employees, Medicare generally pays first and the group plan pays second. That single fact can shape when you enroll in Part B, how your claims are processed, and whether gaps appear in your coverage.

The 20-employee rule, in plain English

Medicare uses employer size to decide who pays first when you have both Medicare and a group health plan tied to current work. The rule works like this:

• 20 or more employees: the group health plan is the primary payer; Medicare is secondary.
• Fewer than 20 employees (and not part of a multi-employer plan where at least one employer has 20 or more): Medicare is primary; the group plan is secondary.

"20 or more employees" has a specific federal definition: the employer had 20 or more employees for each working day in each of 20 or more calendar weeks in the current or preceding calendar year. Part-time workers count. If you're unsure where your employer lands, ask your HR or benefits contact directly — they should know.

For people under 65 who have Medicare due to disability, the threshold is different: 100 employees. Below 100 (with no multi-employer plan at 100 or more), Medicare pays first.

Why this matters at a small employer

Medicare.gov warns that when the employer has fewer than 20 employees, the job-based plan may not pay for services if you don't also have Medicare Part A and Part B. In other words, because the group plan is the secondary payer, it may only cover what Medicare would have paid — so if you skip Part B, you could be left owing the primary share yourself.

That's the practical punchline: at a small employer, enrolling in both Part A and Part B at 65 is usually the safe move. Talk with your benefits administrator so you understand exactly how your plan coordinates with Medicare.

Enrollment timing still works in your favor

Here's a piece of good news: even though Medicare pays first at a small employer, your coverage still counts as "coverage based on current employment" for enrollment purposes. According to Medicare.gov, that means you can sign up for Medicare any time while you (or your spouse) are still working for that employer, or during the 8 months after the job ends or the coverage ends — whichever comes first.

That Special Enrollment Period helps you avoid the late-enrollment penalties that would otherwise apply if you delayed Part B without qualifying coverage.

Multi-employer plans and the Small Employer Exception

Some small businesses participate in a multi-employer group health plan — think union plans or association plans. In those cases, if at least one participating employer has 20 or more employees, the plan generally pays primary for everyone.

There is, however, a federal "Small Employer Exception." A multi-employer plan can ask Medicare's Benefits Coordination & Recovery Center for approval to have Medicare pay first for specifically named individuals who are tied to a participating employer with fewer than 20 employees. The exception applies only to people entitled to Medicare based on age (not disability), and approvals are prospective — they don't reach back to past claims. Your plan administrator would handle this request; it isn't something you file yourself.

Equal-benefit rules at larger employers

If you work at an employer with 20 or more employees, federal law requires the employer to offer workers age 65 and older the same health benefits, under the same conditions, as workers under 65. If the employer covers spouses, spouses 65 and older must be offered the same coverage as younger spouses. You should not be pushed off the group plan simply because you've become Medicare-eligible.

Part D and the bigger picture

Whether or not you take Part B right away, think about prescription drug coverage too. If your employer plan's drug coverage is "creditable," you can usually delay Part D without penalty. If it isn't, you may want Part D sooner.

A few national Part D facts for 2027: the out-of-pocket cap is $2,400 (up from $2,100 in 2026), the maximum allowed plan deductible is $700, and the base beneficiary premium used in the late-enrollment penalty calculation is $41.33. Actual plan premiums vary.

Annual Enrollment for 2027 runs October 15 through December 7, 2026, with changes effective January 1, 2027. Social Security announced a 3.6% cost-of-living adjustment for benefits payable starting in January 2027. The 2027 Part B standard premium and deductible, and the 2027 IRMAA income brackets, have not yet been announced; CMS typically releases those figures in the fall.

If you have Medicaid or qualify for Extra Help, you have a monthly Special Enrollment Period to move to Original Medicare with a stand-alone Part D plan or switch stand-alone plans. Full-benefit dual-eligible individuals can also join an integrated Dual Special Needs Plan (D-SNP) in any month.

Original Medicare + Medigap, or Medicare Advantage?

If you do move to Medicare, you'll generally choose between Original Medicare (often paired with a Medigap policy and a stand-alone Part D plan) and Medicare Advantage. Each has trade-offs. Original Medicare lets you see any provider nationwide who accepts Medicare, and Medigap can reduce out-of-pocket costs, but you pay separate premiums for Medigap and Part D. Medicare Advantage bundles coverage (often including drug coverage) and may include extra benefits, but typically uses provider networks and prior authorization. Neither is "better" — it depends on your providers, medications, travel habits, and budget.

Where to go next

For the most current rules, forms, and plan-finder tools, visit Medicare.gov or call 1-800-MEDICARE (1-800-633-4227), available 24 hours a day, 7 days a week. If you work for a small employer, confirm with your HR team how the plan coordinates with Medicare — and get it in writing if you can.