Medicare Advantage

Medicare Advantage Open Enrollment: What Charleston Can Change by March 31

Charleston, S.C. — If you enrolled in a Medicare Advantage plan last fall and are already second-guessing your choice, you have a window to fix it. The Medicare Advantage Open Enrollment Period runs January 1 through March 31, and it gives Charleston-area residents one more chance to adjust their coverage before it locks in for the rest of the year.

This isn't the same as the busier Annual Enrollment Period that ended December 7. The rules here are narrower — but for people who feel their current plan isn't the right fit, this stretch can matter a lot.

What the Open Enrollment Period actually is

The Medicare Advantage Open Enrollment Period (sometimes shortened to MA-OEP) is a three-month window built into the calendar every year. It exists so that people who are already in a Medicare Advantage plan have a chance to correct course if the plan they picked isn't working out.

According to the Centers for Medicare & Medicaid Services (CMS), this window is only open to people who are already enrolled in a Medicare Advantage plan as of January 1. It is not a general enrollment period for everyone with Medicare.

What Charleston residents can change between Jan. 1 and March 31

If you are enrolled in Medicare Advantage on January 1, you can use this window to do one of the following:

• Switch to a different Medicare Advantage plan (with or without drug coverage).
• Drop your Medicare Advantage plan and return to Original Medicare (Part A and Part B).
• If you go back to Original Medicare, you can also join a stand-alone Part D prescription drug plan.

You can only make one change during this period, and it takes effect the first day of the month after the plan receives your request.

What you cannot do in this window

Just as important — a few things are off-limits:

• You cannot switch from Original Medicare into a Medicare Advantage plan during MA-OEP.
• You cannot join a Part D drug plan if you are staying on Medicare Advantage without drug coverage. (There are separate rules for that.)
• You cannot use this window to enroll in Medicare for the first time.

If none of the allowed moves fit your situation, you may need to wait until the next Annual Enrollment Period (October 15 – December 7) or qualify for a Special Enrollment Period.

Why this matters in Charleston County

Charleston is in Charleston County, where Medicare Advantage plans are offered by multiple carriers, and networks, drug lists, and extra benefits vary from plan to plan. Someone who signed up in December may have since discovered their preferred doctor at MUSC Health or Roper St. Francis isn't in-network, or that a prescription is on a different tier than expected. Those are exactly the kinds of surprises the MA-OEP is designed to address.

Because plan availability is set at the county level, any comparison you do — on Medicare.gov or with a licensed advisor — should be based on your Charleston County ZIP code, not a general South Carolina search.

2027 program-level facts worth knowing

Whether you switch or stay, a few numbers apply across all Medicare drug coverage in 2027:

• The Part D out-of-pocket cap is $2,400 for the year. Once you hit it, you pay $0 for covered drugs the rest of the year.
• The Part D deductible cannot exceed $700 in 2027.
• The old "donut hole" coverage gap has been eliminated as of 2025. Part D now has three phases instead of four.
• The Medicare Prescription Payment Plan lets you spread your drug costs into monthly payments instead of paying large amounts at the pharmacy counter.
• IRMAA surcharges — the higher-income adjustments on Part B and Part D — begin above $109,000 in income for a single filer in 2026.

These are program-level rules from CMS and apply no matter which plan you choose.

How to make a change the right way

Before you switch, do three things:

1. Check the plan's provider network for the doctors and hospitals you actually use. 2. Check the drug formulary for every prescription you take, at the pharmacy you use. 3. Look at total yearly costs, not just the monthly premium — deductibles, copays, and drug costs matter more for most people.

Star Ratings, published by CMS, can also give you a sense of a plan's quality and member experience. They are one data point among several, not a stand-alone verdict.