Medicare Advantage

Sioux City Medicare 2027: Key AEP Dates

SIOUX CITY, Iowa — If you live in Sioux City and you're sorting through your Medicare choices for 2027, the calendar matters as much as the count. Woodbury County had 28 Medicare Advantage plans available in 2026, according to CMS Plan Finder data — but whether you can actually pick one, switch one, or drop one depends entirely on which enrollment window you're in. The 2027 lineup is in each plan's ANOC and on Medicare.gov's Plan Finder.

Here's a plain-English guide to the dates that shape your options.

The main window: Oct. 15 – Dec. 7

This is the Annual Enrollment Period, often called AEP or the fall Open Enrollment. It's the broadest window of the year and the one most Sioux City residents use.

During AEP you can:

• Join a Medicare Advantage plan for the first time.
• Switch from one Medicare Advantage plan to another.
• Drop Medicare Advantage and go back to Original Medicare.
• Join, switch, or drop a Part D drug plan.

Any change you make takes effect Jan. 1, 2027. If Dec. 7 passes and you haven't acted, your current coverage generally rolls into next year as-is — with whatever premium, network, and drug list changes your plan announced in its Annual Notice of Change letter (the ANOC that arrived in September).

The do-over window: Jan. 1 – March 31

The Medicare Advantage Open Enrollment Period is a second chance, but it's narrower and only for people already enrolled in a Medicare Advantage plan on Jan. 1.

In this window you can make one change:

• Switch to a different Medicare Advantage plan, or
• Drop Medicare Advantage and return to Original Medicare (and add a stand-alone Part D plan if you go that route).

You cannot use this window to join Medicare Advantage for the first time if you were on Original Medicare on Jan. 1. And you only get one switch — not unlimited shopping.

One local note: CMS data showed 0 stand-alone Part D plans listed for Woodbury County in the 2026 landscape file. If you're thinking about leaving Medicare Advantage, confirm your 2027 drug coverage options on medicare.gov before making the move.

When you first become eligible

Turning 65 in 2026 or 2027? Your Initial Enrollment Period is a seven-month window — the three months before your 65th birthday month, the birthday month itself, and the three months after. This is separate from AEP and it's your first shot at signing up for Part A, Part B, a Medicare Advantage plan, or a Part D plan.

Missing this window can mean lifelong late-enrollment penalties for Part B and Part D, so it's the one date you don't want to let slide.

Special Enrollment Periods

Life doesn't always line up with the calendar. You may qualify for a Special Enrollment Period (SEP) if you:

• Move out of your plan's service area (a move across county or state lines can trigger this).
• Lose employer or union coverage.
• Qualify for Medicaid or Extra Help.
• Live in a nursing facility.

SEPs generally give you about two months to act. If you think one applies to you, call 1-800-MEDICARE to confirm before assuming.

What if you miss a window?

For most people, missing AEP means waiting until the following Oct. 15 — unless an SEP applies. Missing the Jan. 1 – March 31 window means your current Medicare Advantage plan stays put through the rest of the year.

A few program-level facts worth knowing while you plan:

• The Part D out-of-pocket cap is $2,100 in 2026 and $2,400 in 2027.
• The Part D maximum deductible is $615 in 2026 and $700 in 2027.
• The old coverage gap ("donut hole") was eliminated in 2025; Part D now has three phases.
• The Medicare Prescription Payment Plan lets you spread drug costs over monthly installments if you opt in.
• IRMAA surcharges on Part B and Part D begin above $109,000 in income for a single filer in 2026.

Where to get help in Sioux City

You don't have to sort this out alone. Free, unbiased help is available:

• medicare.gov/plan-compare — the official Plan Finder, which shows every plan available in Woodbury County.
• 1-800-MEDICARE (1-800-633-4227), 24 hours a day.
• Iowa SHIIP (Senior Health Insurance Information Program) — free one-on-one counseling from trained volunteers, with no ties to any insurance company.