Medicare 2026

Medicare in Sioux City: The Dates That Decide Your Choice

SIOUX CITY, Iowa — For people turning 65 in Woodbury County, the choice between Original Medicare with a Medigap policy and a Medicare Advantage plan often gets framed as a benefits question. It is really a timing question. The calendar decides what you can join, what you can switch to later, and — this is the part that catches people — whether a Medigap insurer can ask you health questions before saying yes.

Why the structural choice is really a timing choice

Original Medicare (Parts A and B) is the federal program. A Medigap policy is separate, sold by a private insurer, and it helps pay the deductibles and coinsurance Original Medicare leaves behind. Most people who go this route also add a stand-alone Part D drug plan.

Medicare Advantage (Part C) is different in shape. A private plan takes over your Part A and Part B coverage, usually rolls in drug coverage, and typically uses a network of doctors and hospitals.

You can move between these two worlds — but only during specific windows, and only under specific rules. That is where the dates matter.

The Medigap window most people only get once

Here is the piece Sioux City readers most often learn too late. Your Medigap Open Enrollment Period is a six-month window that begins the month you are 65 or older and enrolled in Part B. During those six months, an insurer selling Medigap in Iowa must sell you any policy it offers at its best available rate, regardless of your health history.

After that window closes, in most cases insurers can use medical underwriting. That means they can look at your health and decide whether to offer you a policy, what to charge, or whether to say no. A few limited “guaranteed issue” situations exist later — for example, if certain plans end coverage — but they are narrow.

This is why the Medigap decision feels heavier than the Advantage decision. If you start with Medicare Advantage and later want to switch to Original Medicare plus Medigap, your ability to get a Medigap policy at all may depend on your health.

The fall window everyone shares: Oct. 15 – Dec. 7

The Annual Enrollment Period, sometimes called AEP, runs from October 15 through December 7 each year. During AEP you can:

• Join, drop, or switch a Medicare Advantage plan.
• Join, drop, or switch a stand-alone Part D drug plan.
• Move from Original Medicare to Medicare Advantage, or the other way around.

Changes you make during AEP take effect January 1. This is the busiest and broadest window, and it is the one to circle on the calendar if you already have Medicare.

Two important limits: AEP does not, by itself, guarantee you a Medigap policy. And if you are choosing a Part D plan, remember the 2027 program-level rules — a maximum deductible of $700 and a hard $2,400 cap on what you pay out of pocket for covered drugs. The old coverage gap, or “donut hole,” was eliminated in 2025.

The winter window that trips people up: Jan. 1 – March 31

The Medicare Advantage Open Enrollment Period runs January 1 through March 31. It is only for people who are already in a Medicare Advantage plan on January 1. During this window you can:

• Switch to a different Medicare Advantage plan.
• Drop your Advantage plan and return to Original Medicare, and pick up a stand-alone Part D plan if you need drug coverage.

What it does not do: it does not guarantee you a Medigap policy on the way out. If you drop your Advantage plan in February, whether a Medigap insurer will sell to you still depends on Iowa’s underwriting rules and any special protections that apply to your situation.

You get one change during this window. Use it thoughtfully.

What happens if you miss a window

Missing your Initial Enrollment Period for Part B can bring a late enrollment penalty that lasts as long as you have Part B. Missing your chance to enroll in Part D when you were first eligible — and going without other creditable drug coverage — can bring a Part D late enrollment penalty added to your premium for as long as you have Part D. Missing your six-month Medigap window does not create a penalty, but it can change what policies you qualify for later.

If your income is above $109,000 as a single filer in 2026, an IRMAA surcharge may be added to your Part B and Part D premiums. That is set by the IRS data Social Security uses, not by the plan you choose.

How Woodbury County fits in

Sioux City is in Woodbury County, and Medicare Advantage and Part D plan availability is set at the county level. That means the menu of plans a Sioux City resident sees is the Woodbury County menu. You can compare what is offered for your ZIP code using the Plan Finder at medicare.gov. Local, unbiased help is also available from Iowa SHIIP, the state’s State Health Insurance Assistance Program, which offers free counseling to Medicare beneficiaries.