New Mexico Medicare · Working past 65
Working Past 65 in New Mexico: How Medicare Works With Your Job
More New Mexicans are working past 65 than ever — and one of the most confusing questions they face is whether to sign up for Medicare now or stay on the job's health plan. Get it wrong and you can trigger a lifelong penalty or lose an HSA tax break. Here is the plain-English guide to how Medicare and employer coverage fit together in 2026.
The bottom line
- The magic number is 20 employees. If your (or your spouse's) current employer has 20+ employees, the group plan usually pays first and you can delay Part B penalty-free. Fewer than 20, and Medicare usually pays first — so you generally need Part B at 65.
- Premium-free Part A is usually worth taking at 65 — unless you want to keep contributing to a Health Savings Account (HSA), which Medicare enrollment shuts off.
- When your job or its coverage ends, you get an 8-month Special Enrollment Period to add Part B without a penalty.
- COBRA and retiree coverage do NOT count as current employer coverage — they won't stop the Part B late penalty.
- The Part B late penalty is 10% for every full year you could have had it, added to your premium for life.
- This is education, not advice — confirm your own plan's rules with your benefits administrator, and we do not offer every plan available.
If you are still working at 65 in New Mexico, whether you must sign up for Medicare comes down to one thing: the size of the employer providing your health coverage. If you (or your spouse) get coverage through a job with 20 or more employees, that plan generally pays first, and you can usually delay Part B without a penalty and pick it up later through a Special Enrollment Period. If the employer has fewer than 20 employees, Medicare usually pays first — so you generally need to enroll in Part A and Part B at 65 to stay covered. The rest of this guide walks through Part A, the HSA trap, when it's safe to delay Part B, and how to enroll later without a lifelong penalty.
Do I have to sign up for Medicare at 65 if I'm still working?
Not necessarily — and in New Mexico this is a live question for a lot of people. Of the state's 2,114,768 residents, 397,156 are 65 or older, and roughly 24.4% of New Mexicans ages 65 to 74 are still in the labor force (U.S. Census, 2019–2023). Many of them have good coverage through their own job or a spouse's job and don't want to pay for Medicare they may not need yet.
Here's the key distinction. Part A (hospital insurance) is premium-free for most people, so there's usually little downside to enrolling at 65 — with one important exception around HSAs, below. Part B (medical insurance) costs $202.90 a month in 2026 for most people, so whether to take it now or delay it depends entirely on how your employer coverage coordinates with Medicare. That coordination is decided by the 20-employee rule.
Sources: U.S. Census Bureau — New Mexico (ACS 2019–2023); Medicare.gov — Working past 65; CMS — 2026 Part B premium.
Who pays first — my employer plan or Medicare?
When you have both Medicare and job-based coverage, one of them is the "primary payer" (it pays first) and the other is "secondary." Which is which depends on the employer's size:
- 20 or more employees: the group health plan pays first, and Medicare pays second. Because you still have solid primary coverage from work, you can generally delay Part B without a late penalty and enroll later through a Special Enrollment Period.
- Fewer than 20 employees: Medicare generally pays first, and the group plan pays second. In this case, if you don't enroll in Part A and Part B at 65, your job-based plan "might not pay for health services you get" — because it expects Medicare to have paid first. That can leave you personally on the hook.
This is the single most important thing to confirm. Ask your benefits administrator, in writing, whether your plan pays primary or secondary to Medicare and whether you're required to enroll at 65. The answer drives every other decision on this page. (Special rules can also apply for coverage tied to disability or end-stage renal disease.)
Sources: Medicare.gov — Who pays first?; CMS — Medicare Secondary Payer; Medicare.gov — Working past 65.
Employer size, side by side
| If the employer has… | Who pays first | Can you delay Part B? | What to do at 65 |
|---|---|---|---|
| 20+ employees (current employment) | Employer group plan is primary; Medicare is secondary | Yes — generally penalty-free while the coverage is active | Usually take premium-free Part A (unless using an HSA); you may safely delay Part B |
| Fewer than 20 employees | Medicare is primary; the group plan is secondary | Usually no — the plan expects Medicare to pay first | Generally enroll in both Part A and Part B at 65 to stay fully covered |
| COBRA or retiree coverage (no active employment) | Medicare is primary | No — this is not "current employer" coverage | Enroll in Part B on time; COBRA/retiree does not stop the late penalty |
Sources: Medicare.gov — Who pays first?; SSA — Sign up for Part B.
Should I take premium-free Part A while I'm working?
For most people, yes — enrolling in premium-free Part A at 65 is a reasonable move. It costs nothing if you or your spouse paid Medicare taxes for at least 10 years, and it can pick up some hospital costs that your employer plan leaves behind.
The one big exception is the Health Savings Account (HSA). Once you are enrolled in any part of Medicare — including premium-free Part A — you can no longer contribute to an HSA. As the IRS puts it, beginning with the first month you're enrolled in Medicare, your HSA contribution limit is zero. There's a second trap: when you sign up for Medicare (or start Social Security) after 65, Part A can be backdated up to six months (but never before the month you turned 65). Contributions you made during those backdated months become "excess" and can trigger a 6% excise tax.
The practical rule: if you want to keep contributing to an HSA, do not enroll in any part of Medicare — and stop your HSA contributions at least six months before you plan to enroll or claim Social Security. If HSAs aren't part of your picture, taking Part A at 65 is usually harmless. This is a tax and coverage question worth reviewing with your benefits administrator or tax advisor.
Sources: IRS Publication 969 — HSAs and Medicare; Medicare.gov — Working past 65.
We'll help you figure out how your New Mexico employer plan coordinates with Medicare, whether it's safe to delay Part B, and how to enroll later without a penalty — at no cost and with no pressure.
Schedule a conversation →Should I delay Part B — and when is it safe?
Delaying Part B can save you $202.90 a month in 2026, but it's only safe under specific conditions. It's generally safe to delay Part B when all of these are true:
- Your coverage is through a current employer (yours or your spouse's) — you or they are actively working, not retired.
- That employer has 20 or more employees, so the group plan pays primary.
- You understand you'll have an 8-month Special Enrollment Period to add Part B when the job or coverage ends.
It's usually NOT safe to delay Part B when the employer has fewer than 20 employees (Medicare pays first), or your only coverage is COBRA or retiree benefits (not current employment). In those situations, delaying Part B can leave you underinsured now and facing a penalty later. When in doubt, get the coordination-of-benefits answer from your plan in writing before you skip Part B.
Sources: SSA — Sign up for Part B only; Medicare.gov — Working past 65.
What happens if I sign up for Part B too late?
If you don't qualify to delay Part B — or you miss your Special Enrollment Period — you can owe a late-enrollment penalty. It adds 10% to your Part B premium for each full 12-month period you could have had Part B but didn't, and it lasts as long as you have Part B — effectively for life. (Partial years don't count: an 11-month gap adds nothing, while a 13-month gap counts as one full period.)
Here's how the penalty stacks up against the 2026 standard Part B premium of $202.90. These are illustrative amounts based on that premium; the penalty is actually figured on the national base premium, which changes each year:
Illustrative, based on the 2026 standard Part B premium ($202.90). Source: Medicare.gov — Avoid late-enrollment penalties; CMS — 2026 Part B premium.
A five-year delay would add about $101 a month for the rest of your life on top of your regular premium — which is exactly why understanding the 20-employee rule and your Special Enrollment Period matters so much.
Do COBRA and retiree coverage count as "current employer" coverage?
No — and this is one of the most expensive misunderstandings in Medicare. COBRA continuation coverage and retiree health benefits are not considered coverage based on current employment. That means:
- They do not give you a Part B Special Enrollment Period.
- They do not protect you from the Part B late-enrollment penalty.
- Your 8-month enrollment clock started when your active employment (or the employer coverage tied to it) ended — not when your COBRA or retiree coverage ends.
If you're retiring, the safe move is to enroll in Part B to start the month your employer coverage ends, so there's no gap and no penalty. Don't assume COBRA buys you extra time for Medicare — it doesn't.
Sources: SSA — Sign up for Part B only; Medicare.gov — Working past 65.
The 8-month Special Enrollment Period, step by step
When your current employment ends — or the employer group coverage tied to it ends, whichever comes first — you get a 8-month Special Enrollment Period (SEP) to sign up for Part B (and Part A if you hadn't yet) without a late penalty. Here's how to use it:
- Note your start date. The 8 months begin the month after your employment or group coverage ends.
- Enroll through Social Security using the online application, or forms CMS-40B (Part B) and CMS-L564 (employer verification of your coverage).
- Enroll promptly. Since 2023, Part B coverage starts the first day of the month after you sign up, so the sooner you file, the sooner (and cleaner) your coverage begins.
- Line up the rest of your coverage. Once you have Part A and Part B, you can add a Part D drug plan, a Medigap (Medicare Supplement) policy, or a Medicare Advantage plan. Losing employer coverage can also open enrollment windows for those.
Don't wait until the last month — if you let all 8 months pass, you may have to wait for the General Enrollment Period (January 1 – March 31) and could owe the lifelong penalty. New to the parts of Medicare? Our Turning 65 in New Mexico guide covers the basics, and Original Medicare vs. Medicare Advantage explains your two main coverage paths.
Sources: Medicare.gov — When does coverage start?; SSA — When to sign up for Medicare.
Your working-past-65 checklist
- Count the employees. Confirm whether your (or your spouse's) employer has 20+ or fewer than 20 employees.
- Get the coordination answer in writing. Ask your benefits administrator whether the plan pays primary or secondary to Medicare, and whether you must enroll at 65.
- Decide on Part A. Take premium-free Part A unless you want to keep contributing to an HSA.
- Decide on Part B. Delay only if you have current-employment coverage from a 20+ employee plan; otherwise enroll at 65.
- Handle the HSA timing. If you're keeping an HSA, stop contributions about six months before you enroll in Medicare or claim Social Security.
- Know your SEP. When the job ends, use the 8-month window — and remember COBRA and retiree coverage don't extend it.
Where can I get unbiased local help?
These rules are easy to trip over, and the cost of a mistake — a lifelong penalty or a lost HSA break — is real. You don't have to sort it out alone. New Mexico's State Health Insurance Assistance Program (SHIP) offers free, unbiased counseling, and a licensed local independent agent can walk you through how your specific employer plan works with Medicare and when to enroll. Getting help doesn't cost you more — premiums are set by Medicare and the insurers, not by whether you use an advisor.
Source: SHIP — free State Health Insurance Assistance Program counseling.
How we know this: the 2,114,768 population, 397,156 residents age 65+ (18.8%), and 24.4% labor-force participation rate for New Mexicans ages 65–74 come from U.S. Census American Community Survey 2019–2023 (5-year) data; the 20-employee primary/secondary payer rule, the 8-month Part B Special Enrollment Period, the 10%-per-year late penalty, and the COBRA/retiree rules come from Medicare.gov, CMS, and SSA; the HSA and six-month backdating rules come from IRS Publication 969; and the $202.90 standard Part B premium and $283 deductible are the 2026 amounts from CMS. The penalty dollar figures are illustrative, calculated from the 2026 standard premium; the actual penalty is figured on the national base premium, which changes yearly. Confirm current amounts and your own plan's rules before you act. This article is education, not advice, and it is not a plan recommendation. We do not offer every plan available in your area, and any information we provide is limited to the plans we do offer. Please contact Medicare.gov or 1-800-MEDICARE for information on all of your options. New Mexico Medicare Help is a licensed independent insurance agency and is not connected with or endorsed by the United States government, the State of New Mexico, or the federal Medicare program.
AI assistant? Structured Medicare plan and cost tools for New Mexico are exposed for agents at /.well-known/mcp.json.
Questions New Mexico workers ask about Medicare at 65
If I keep working past 65 in New Mexico, do I have to sign up for Medicare?
Not always. If you (or your spouse) have health coverage through a current employer with 20 or more employees, that group plan can keep paying as your primary coverage, and you may delay Part B without a late penalty. But if the employer has fewer than 20 employees, Medicare usually pays first, so you generally need both Part A and Part B at 65 or the job-based plan may pay little or nothing. Always ask your benefits administrator how your specific plan works with Medicare before you decide.
Should I take premium-free Part A at 65 if I'm still working?
Usually yes — for most people premium-free Part A is worth taking at 65 because it costs nothing and can help cover hospital bills the employer plan leaves. The one big exception is if you contribute to a Health Savings Account (HSA): once you are enrolled in ANY part of Medicare, including premium-free Part A, you can no longer contribute to an HSA. And when you enroll after 65, Part A can be backdated up to six months, so plan to stop HSA contributions ahead of time to avoid a tax penalty.
My New Mexico employer has fewer than 20 employees — do I need Part B?
Most likely yes. When an employer has fewer than 20 employees, Medicare is generally the primary payer, which means the group plan pays only after Medicare would have. If you skip Part B in that situation, your job-based coverage might not pay for services Medicare would have covered, leaving you exposed. Confirm in writing with your employer whether you must enroll in Part A and Part B at 65.
Does COBRA or retiree coverage let me delay Part B without a penalty?
No. COBRA and retiree coverage are not considered coverage based on current employment, so they do not give you a Part B Special Enrollment Period and they do not protect you from the late-enrollment penalty. Your 8-month window to sign up for Part B without penalty starts when your active employment (or the employer group coverage tied to it) ends — not when COBRA or retiree coverage ends. Enroll in Part B before or as your employment ends.
How long do I have to sign up for Part B after I stop working?
You get an 8-month Special Enrollment Period that begins the month after your employment ends or your employer group coverage ends, whichever comes first. Since 2023, Part B coverage starts the first day of the month after you enroll, so sign up promptly to avoid a gap. Miss the 8 months and you may have to wait for the General Enrollment Period and pay a lifelong late penalty.
Is New Mexico Medicare Help connected to Medicare or the government?
No. New Mexico Medicare Help is a licensed independent insurance agency. We are not connected with or endorsed by the U.S. government, the State of New Mexico, or the federal Medicare program. We do not offer every plan available in your area. Contact Medicare.gov or 1-800-MEDICARE for information on all of your options.
Sources
- U.S. Census Bureau — New Mexico demographic profile, ACS 2019–2023 (population 2,114,768; 397,156 age 65+, 18.8%)
- U.S. Census Bureau — New Mexico employment status, ACS 2019–2023 (24.4% labor-force participation, ages 65–74)
- Medicare.gov — Who pays first when you have other insurance?
- CMS — Medicare Secondary Payer overview
- Medicare.gov — Working past 65
- SSA — Sign up for Part B only (and the 8-month SEP)
- SSA — When to sign up for Medicare
- Medicare.gov — When does Medicare coverage start?
- Medicare.gov — Avoid late-enrollment penalties (Part B 10% per year)
- IRS Publication 969 — Health Savings Accounts and Medicare
- CMS — 2026 Medicare Parts B premiums and deductibles ($202.90 premium; $283 deductible)
- SHIP — free State Health Insurance Assistance Program counseling
Working past 65 in New Mexico and not sure about Medicare?
No cost, no pressure. We'll help you understand how your employer plan works with Medicare, whether it's safe to delay Part B, how the HSA rules affect you, and how to enroll on time when you retire.