Medicare

Medicare 102: When & How to Enroll

Deborah Meyer, and Mark Angus Meyer

July 28, 2026

When & How to Enroll in Medicare: A Complete Guide for Wyoming, South Dakota, and North Dakota

Written by the Meyer Family Team at Spearfish Insurance Brokerage — licensed Medicare agents serving South Dakota, North Dakota, and Wyoming, rated 4.8 stars on Google, with thousands of clients served across the region.

Medicare enrollment can feel overwhelming, with different windows, rules, penalties, and the decision to delay Part B while covered under employer health insurance. This guide breaks down the essentials — but if you’d rather skip the research and just talk to someone, that’s what we’re here for. Give us a call at 605.722.1965, and we’ll ask a few questions and point you in the right direction, no homework required.

If you already know you want to enroll in Medicare, skip to section 2 for enrollment windows and section 3 for how to apply.

Section 1: Working Past 65 — Deciding Between Employer Coverage and Medicare

If you’re still working at 65, whether you need Part B right away depends largely on the size of your employer:

20 or more employees: Medicare stays secondary to your group coverage, so you can safely delay Part B and enroll penalty-free later using a Special Enrollment Period once you leave that job or coverage ends.
Fewer than 20 employees: Medicare becomes primary, so delaying Part B often creates real coverage gaps and unpaid claims. You may also accrue late enrollment penalties if delay Part B and your employer coverage is not "creditable."

How to know if your coverage is creditable: Each fall, insurers are required to send a Notice of Creditable Coverage stating whether your plan meets Medicare’s standard. When in doubt, ask your HR department directly and get the answer in writing for your records.

Beyond the rules — do the math.

Compare your group plan’s deductible, out-of-pocket maximum, and premium contribution against what Original Medicare plus a Medigap or Advantage plan would cost. We can provide current quotes on a quick call with us at no cost: 605.722.1965.

And don’t forget prescriptions: drug coverage has its own separate creditable coverage test from medical coverage, so it’s possible to have creditable medical coverage but non-creditable drug coverage without realizing it.

Section 2: Understanding Your Enrollment Windows

The Initial Enrollment Period (most common)

Your Initial Enrollment Period (IEP) is a seven-month window built around your 65th birthday. It starts three months before the month you turn 65, includes your birthday month, and runs three months after — seven months total to get enrolled without a penalty.

Enrolling Medicare Through Disability

Turning 65 isn’t the only way onto Medicare. Several disability pathways can get you enrolled earlier:

Social Security Disability (SSDI): After 24 months of collecting SSDI benefits, Medicare coverage starts automatically in month 25 — no application needed.
End-Stage Renal Disease (ESRD): Coverage typically begins on the first day of the fourth month of dialysis treatment. For example: If you begin dialysis anytime in January, coverage starts April 1. An important exception: if you do at-home dialysis training, coverage can start as early as the first month.
ALS (Lou Gehrig’s Disease): No waiting period at all. Coverage begins the very first month you’re entitled to SSDI benefits, recognizing how quickly this disease progresses.

The General Enrollment Period

If you miss your Initial Enrollment Period (IEP) and don’t qualify for a Special Enrollment Period (SEP), you get another chance during the General Enrollment Period (GEP), which runs January 1 through March 31 every year. Coverage starts the first day of the month after you enroll. Keep in mind that enrolling here doesn’t erase a late enrollment penalty if you were otherwise eligible and didn’t have creditable coverage in the meantime — so it’s a safety net, not a way around the penalty.

Section 3: How to Actually Enroll

Once you know it’s time to sign up, we recommend submitting your enrollment at least two months prior to the month you'd like to begin Medicare, as processing times can lag considerably.

There are a few ways to enroll. We've listed them in order of ease according to our clients:

Online through your ssa.gov account My Social Security portal — the option to apply is at the bottom of your account landing page
Online without a full portal account at ssa.gov on the Sign up for Medicare Page
By phone, calling Social Security directly at 800.772.1213
In person at your local Social Security office

The automatic exception: If you’re already collecting Social Security retirement or disability benefits at least four months before you turn 65, you’ll be automatically enrolled in both Part A and Part B.

Side note: We — Deborah and Mark — are certified National Social Security Advisers. You can also lean on us for Social Security-specific questions, not just Medicare.

Section 4: Late Enrollment Penalties — and How They CanSometimes Be Undone

Missing your enrollment window comes with real costs:

Part B penalty: 10% added to your premium for every full 12-month period you were eligible but didn’t enroll — and it’s permanent for as long as you have Part B.
Part D penalty: A smaller monthly penalty based on the national base premium, also generally permanent.

As seasoned agents, we have some lesser-known loopholes to get you relief from penalties:

Equitable relief for Part B: If a federal employee (such as someone at Social Security) gave you incorrect information that caused you to delay, you may be able to get the penalty reduced or removed by writing a detailed letter to your local Social Security office.
Extra Help / LIS: Qualifying for the Extra Help (Low-Income Subsidy) program permanently erases an existing Part D penalty.
Turning 65 off disability: If you’re under 65 and carrying a Part D penalty from Medicare due to disability, that penalty is erased once you turn 65 and get a fresh Initial Enrollment Period.

These situations are nuanced and case-by-case — if you think you might qualify for relief, that’s exactly the kind of question we can help sort through, wherever you are in Wyoming, South Dakota, or North Dakota.

Section 5: Why Work With a Local Agent

We know the local networks

Understanding how Medicare works with our region's hospitals and clinics isn’t always obvious from a call center — we know our region.

A real person, face to face

You can sit down with us directly instead of getting bounced around a phone tree.

Your hard-earned dollars stay local

Working with a local agency costs you exactly the same as calling the carrier directly — agents are paid by the carrier, not by you. The difference is that your business supports an agency that’s part of your community. In return, we support you and your interests. Keep your dollars circulating in the local economy instead of sending them away.

The Bottom Line

This guide covers a lot of ground, and Medicare rules can get complicated fast. But you don’t have to figure it all out on your own. Give us a call, sit down with us, or send us a message — we’ll ask a few questions about your situation and help you figure out exactly what you need, without you having to become a Medicare expert yourself.

Areas We Serve

Spearfish Insurance Brokerage is based in Spearfish, South Dakota, and most active in the counties closest to home: Lawrence, Meade, Butte, Pennington, Custer, Fall River, Stanley, Hughes, Jones, and Jackson counties in South Dakota, along with Crook and Weston counties in Wyoming.

Beyond our core area, we serve thousands of clients across every county in South Dakota, North Dakota, and Wyoming. We have deep client relationships and plan knowledge across that footprint.

About Your Local Agents

Deborah Meyer has been a licensed insurance agent since 2001, with over 20 years of experience. She is a National Social Security Advisor and a prominent educator on Medicare and Social Security throughout the region, having served roughly 10,000 clients across South Dakota, North Dakota, and Wyoming.

Mark Meyer has been licensed for two years, bringing a corporate leadership background into the family business. He holds an MBA from the Stern School of Business at NYU and has already helped over 1,000 clients.

Kaylee Rust has been licensed for three years and is a Medicare expert in her own right. We hear it all day when we answer our phones: "I'm calling for Kaylee."

Together, our team is rated 4.8 stars on Google, reflecting the trust we’ve built with clients across South Dakota, North Dakota, and Wyoming.

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