Medicare Supplement

Why Medigap's Six-Month Window Matters in Lafayette

Lafayette, Colorado — For people turning 65 here in Boulder County, one Medicare decision has a clock on it that most others do not. It is called the Medigap Open Enrollment Period, and it is the single stretch of time when an insurance company selling Medigap in Colorado must sell you a policy on the same terms as everyone else your age — no matter what your health history looks like.

Miss it, and the rules change. That is why it deserves a spot on the calendar the day Part B begins.

What the six-month window actually is

Medigap — also called Medicare Supplement Insurance — is a private policy that helps pay some of the costs Original Medicare leaves behind, such as coinsurance and deductibles. It works alongside Part A and Part B.

Your Medigap Open Enrollment Period begins the first month you are both 65 or older AND enrolled in Medicare Part B. It lasts six months. That is the federal rule, and it applies whether you live in Lafayette, elsewhere in Boulder County, or across the country.

During those six months, you have what Medicare calls a guaranteed issue right. In plain English: an insurer selling Medigap policies in your area cannot refuse to sell you one, cannot make you wait because of a pre-existing condition (in most cases), and cannot charge you a higher premium because of your health.

Why this window matters more than most Medicare deadlines

Medicare has several enrollment periods — the Annual Enrollment Period from October 15 to December 7, the Medicare Advantage Open Enrollment Period from January 1 to March 31, and others. Most of those come back every year.

The Medigap Open Enrollment Period does not. It happens once, tied to your 65th birthday and your Part B start date. That is what makes it different, and that is why Medicare and consumer advocates flag it so often.

What changes after the six months end

Once your window closes, insurers in most states — including Colorado — are generally allowed to use medical underwriting when you apply for a Medigap policy. That means they can:

• Ask health questions
• Charge a higher premium based on your health
• Delay coverage for certain pre-existing conditions
• Turn down your application

There are a few limited situations, called guaranteed issue rights, where you can still buy certain Medigap policies without underwriting after your window closes — for example, if you lose other coverage under specific circumstances. But these are narrow, and they do not replace the broad protection of the six-month open enrollment window.

How Medigap fits with the rest of your Medicare choices

Medigap only works with Original Medicare (Part A and Part B). You cannot use a Medigap policy to pay costs under a Medicare Advantage plan. So the choice you make around age 65 — Original Medicare with a Medigap and a stand-alone Part D drug plan, or a Medicare Advantage plan — shapes what your Medigap window is worth to you.

A few 2026 program facts worth knowing as you plan:

• Part D has a new out-of-pocket cap of $2,100 for 2026.
• The Part D maximum deductible is $615.
• The old coverage gap (the "donut hole") has been eliminated as of 2025.
• The optional Medicare Prescription Payment Plan lets you spread drug costs across the year.
• Higher-income enrollees may owe IRMAA surcharges; those begin above $109,000 in income for a single filer in 2026.

Lafayette is in Boulder County, where residents have access to Medicare Advantage and Part D plans set at the county level. Medigap policies, by contrast, are regulated at the state level in Colorado.

What to do during your six months

A short checklist for Lafayette residents approaching 65:

1. Confirm the month your Part B coverage starts — that sets your Medigap clock. 2. Decide whether you want Original Medicare plus Medigap, or a Medicare Advantage plan. 3. If you want a Medigap policy, compare the standardized plan letters (like Plan G or Plan N). The benefits within each letter are the same by law across insurers; premiums and customer service vary. 4. Apply before the six-month window ends. 5. Keep written records of your enrollment dates.