Medicare 2026

How Medicare Advantage and Medigap differ for Columbia residents

COLUMBIA, Md. — For people weighing Original Medicare paired with a Medigap policy against a Medicare Advantage plan, the choice often feels like a benefits question. In practice, it's just as much a calendar question. The windows to enroll — and the window to switch back — don't always line up, and missing one can quietly lock in a decision for years.

Columbia is in Howard County, where residents have access to both paths: Original Medicare (Parts A and B) with an optional Medigap supplement and a stand-alone Part D drug plan, or a Medicare Advantage plan (Part C) that bundles hospital, medical, and usually drug coverage through a private insurer. The structural difference matters, but the timing of when you can move between them matters just as much.

The structural difference, in one paragraph

Original Medicare is the federal program. A Medigap policy is private insurance that pays some of what Original Medicare leaves behind — deductibles, coinsurance, and the like — and you add a stand-alone Part D plan for drugs. Medicare Advantage is a private plan that replaces the way you use Original Medicare: same Part A and Part B rights, delivered through the insurer's network and rules, usually with drug coverage built in. You can be in one system or the other, not both. Where the paths really diverge is in when you're allowed to move between them.

The deadline that quietly shapes everything: Medigap Open Enrollment

The single most important date for anyone considering the Original Medicare + Medigap path is your Medigap Open Enrollment Period. It's a one-time, six-month window that begins the month you're 65 and enrolled in Part B. During that window, insurers must sell you any Medigap policy they offer at their standard rate, regardless of your health history.

Miss it, and in most cases insurers can use medical underwriting — meaning they can charge you more, or decline to sell you a Medigap policy at all — outside of certain guaranteed-issue situations. That's why the Medigap decision is really a decision you make near 65, even if you don't feel the consequences until years later.

The annual windows most people know

Two federal windows drive most switching decisions after your initial enrollment:

• Annual Enrollment Period (Oct. 15 – Dec. 7). You can join, drop, or switch a Medicare Advantage plan, and join, drop, or switch a Part D plan. Changes take effect Jan. 1.
• Medicare Advantage Open Enrollment Period (Jan. 1 – March 31). If you're already in a Medicare Advantage plan, you get one chance to switch to a different Advantage plan or drop back to Original Medicare (and add a Part D plan). You can't use this window to move from Original Medicare into Advantage.

Note what's not on that list: a yearly window to buy a Medigap policy. Medigap sits on its own timeline, and that's the trap.

What happens if you switch back later

Say you choose Medicare Advantage at 65, use it for a few years, and then decide you'd rather have Original Medicare with a Medigap policy. You can drop the Advantage plan during the Annual Enrollment Period or the Medicare Advantage Open Enrollment Period. You can pick up a Part D plan at the same time. But the Medigap application is a separate step — and outside of specific "guaranteed issue" rights, the insurer can look at your health.

Maryland has its own rules layered on top of federal law, and a few limited situations (such as certain plan terminations or moves out of a plan's service area) create guaranteed-issue rights. But most people who wait can't count on those. This is the piece of the puzzle a lot of readers don't hear about until they're already trying to make the move.

How Part D deadlines fit in

Part D has its own late-enrollment penalty if you go 63 or more days without creditable drug coverage after you're first eligible, and that penalty stays with you as long as you have Part D. That's true whether your drug coverage comes through a stand-alone Part D plan (the usual pairing with Original Medicare + Medigap) or built into a Medicare Advantage plan.

The Part D annual out-of-pocket cap is $2,100 in 2026 and $2,400 in 2027, and the maximum deductible is $615 in 2026 and $700 in 2027; the old coverage gap is gone. The optional Medicare Prescription Payment Plan lets you spread drug costs across the calendar year in monthly installments instead of paying at the pharmacy counter.

A simple way to think through the timing

Before you pick a path, walk through three questions in order:

1. Am I in, or approaching, my Medigap Open Enrollment window? If yes, understand that this window won't come back automatically. 2. If I choose Medicare Advantage now, am I comfortable that switching back later may involve Medigap underwriting? For some people the answer is a confident yes. For others, that risk changes the math. 3. Do my income and drug list interact with any other deadlines? IRMAA surcharges begin above $109,000 in income for a single filer in 2026, and Part D's late-enrollment penalty is triggered by gaps in creditable coverage.

None of this is about which path is "better." It's about understanding which doors close, and when.