Still employed and approaching 65? You have more options than you think — and more ways to make a costly mistake. Whether your employer has 20 employees or 2,000, the rules are different and the penalties for getting it wrong are permanent. Here's what you need to know.
If you delay Medicare enrollment without qualifying employer coverage, you'll face a permanent 10% late enrollment penalty on Part B for every 12-month period you were eligible but didn't enroll. This penalty is added to your premium for life. Many South Carolinians working for small employers (under 20 employees) don't realize Medicare should have been primary from age 65 — and discover the penalty only when they try to enroll later.
Your Situation Determines Your Options
The most important factor isn't your age — it's how many employees your employer has. Here's how Medicare works in each scenario.
If your employer has 20 or more employees and you're covered under their group health plan, your employer insurance pays first. You can delay enrolling in Medicare Part B — and Part D — without a late penalty, as long as your employer coverage is active.
You may still want to enroll in Part A (hospital coverage), which is free for most people and can act as secondary coverage. But Part B enrollment can wait until you retire or lose group coverage.
If your employer has fewer than 20 employees, Medicare becomes your primary insurer at 65 — whether you enroll or not. Your employer plan becomes secondary and may pay very little if Medicare hasn't paid first.
Delaying enrollment in this situation means gaps in coverage and potential penalties. You should enroll in Medicare Parts A and B during your Initial Enrollment Period — the 7-month window around your 65th birthday.
If you're covered under your spouse's employer plan, the same size rule applies — to your spouse's employer, not yours. If their employer has 20 or more employees, you can generally delay Medicare. If fewer than 20, Medicare should be primary.
Always verify with the plan administrator. The rules for spousal coverage can be complex and vary by plan.
If you're self-employed and buying your own health insurance — through the ACA marketplace or directly from a carrier — that coverage typically doesn't qualify as employer group health coverage for Medicare delay purposes.
You should enroll in Medicare at 65 to avoid the late enrollment penalty. An ACA plan and Medicare can sometimes work together during a transition period, but Medicare should become primary at 65.
What You Need to Know
These are the most commonly misunderstood Medicare rules for people still in the workforce at 65.
Medicare Part A (hospital coverage) is premium-free for most people who've worked 40+ quarters. Even if you're delaying Part B, enrolling in Part A generally makes sense — it can act as secondary coverage at no cost to you.
You have a 7-month window to enroll in Medicare — 3 months before your 65th birthday month, your birthday month, and 3 months after. Missing this window without qualifying coverage can trigger permanent penalties.
When you stop working or lose group health coverage — whichever comes first — you have an 8-month Special Enrollment Period to sign up for Medicare Part B without penalty. Don't wait until COBRA runs out to enroll.
To avoid a Part D late enrollment penalty, your employer's prescription drug coverage must be "creditable" — meaning it covers at least as much as Medicare Part D. Your employer is required to notify you each September whether their plan qualifies.
COBRA is not considered active employer-sponsored group health coverage for Medicare purposes. If you retire and take COBRA instead of enrolling in Medicare, your 8-month Special Enrollment Period clock is still ticking — and COBRA ends the moment you enroll in Medicare anyway.
Every employer plan is different. Before deciding whether to enroll in Medicare or delay, talk to your employer's HR or benefits administrator. Ask specifically: Is Medicare required? How will Medicare coordinate with our plan? Will my coverage change if I enroll in Medicare?
Special Consideration
Health Savings Accounts and Medicare don't mix. Understanding this rule before you enroll can save you from a significant tax penalty.
Once you enroll in any part of Medicare — including Part A — you can no longer contribute to a Health Savings Account. Contributions made after Medicare enrollment are subject to income tax plus a 20% penalty.
Medicare Part A enrollment can be backdated up to 6 months when you apply for Social Security at 65 or later. If you've been contributing to an HSA during that period, those contributions may be considered excess and penalized.
Stop contributing to your HSA at least 6 months before you plan to enroll in Medicare or apply for Social Security benefits — whichever comes first. You can still use your existing HSA balance tax-free for qualified medical expenses including Medicare premiums.
The HSA and Medicare interaction is one of the most commonly mishandled parts of Medicare planning for working adults. Talk to a Medicare agent and your tax advisor before making changes to your enrollment timing.
Before You Turn 65
Use this checklist to make sure you haven't missed anything before your Medicare eligibility window opens.
Common Questions
Questions we hear most often from SC workers approaching 65.
Your Local Medicare Experts
Working past 65 is one of the most complex Medicare situations there is. We help Midlands SC residents navigate it every day — at no cost.
Medicare & Health Insurance Specialist
Jennifer specializes in Medicare — Advantage, Supplement, Part D, and the health insurance side of the working-past-65 equation. She helps Midlands SC residents understand their options clearly and make confident decisions.
Independent Insurance Agent — All Lines
Ben handles the employer coverage, group benefits, and full-picture insurance side. If you need someone who understands both your employer plan and Medicare simultaneously, MIG is the only local agency that covers both.
Don't risk a permanent penalty or a gap in coverage. A free 15-minute call with Jennifer can save you years of overpaying.
Jennifer Mauldin | (843) 509-2462 | jennifer@mauldininsurancegroup.com | Lexington, SC