4 Medicare Enrollment Dates Tennesseans Can’t Afford to Miss This Fall

Medicare has more than one sign-up window, and they’re easy to mix up.

Which one applies to Tennesseans depends on whether you already have coverage or are about to qualify.

Here are the dates to mark so nothing slips by.

Note: This is general information, not insurance or financial advice. Medicare rules, dates and dollar amounts are subject to change, so confirm the details with the Centers for Medicare & Medicaid Services or the Tennessee State Health Insurance Assistance Program.

1. October 15 Open Enrollment Launch

Open enrollment opened October 15 and runs through December 7.

You still have time.

If you’re in a Medicare Advantage Plan, you can switch to a different Medicare Advantage Plan or add or drop its drug coverage.

Original Medicare members can join, drop or switch a drug plan, or move to Medicare Advantage.

Before you choose, add all the prescription drugs you take regularly to Medicare’s plan comparison tool to get the most accurate monthly and yearly cost estimate for each plan.

2. December 7 Open Enrollment Deadline

Medicare open enrollment changes you make by December 7 take effect January 1 of the following year.

The plan you pick also has to get your enrollment request by December 7.

If you mail a paper form, the plan must get it before your enrollment period ends.

If you leave a Medicare Advantage Plan for Original Medicare, you may need to join a separate drug plan.

3. November 1 Initial Enrollment Start

Medicare's Initial Enrollment Period opens on November 1 if you turn 65 in February 2027.

With a February birthday, sign up between November 1 and January 31, and your coverage begins February 1, 2027.

Wait until February or the three months after, and coverage starts the month after you sign up.

A mid-March 2027 birthday opens the window December 1, and a mid-January 2027 birthday opened it October 1.

That's seven months in all, ending three months after the month you turn 65.

If your birthday is the first of the month, it counts as the month before, so a February 1 birthday opens the window October 1.

4. November 30 Initial Enrollment Deadline

You may owe a monthly penalty for as long as you have Medicare Part B if you sign up after your window closes.

If you turned 65 in August 2026 on any day after the 1st, your Initial Enrollment Period ends November 30.

A September birthday after the 1st pushes the deadline to December 31.

An October 1 birthday closes the window December 31, since a first-of-the-month birthday counts as the month before.

Medicare Advantage Open Enrollment, January 1 to March 31

Medicare Advantage Open Enrollment runs January 1 to March 31, and only people already in an Advantage Plan can use it.

It gives those members a second chance to switch Advantage Plans or return to Original Medicare.

Coverage starts the first of the month after the plan gets your request to join.

Changes from open enrollment start January 1, the same day this window opens.

General and Special Enrollment Periods

Medicare's General Enrollment Period runs from January 1 to March 31 each year.

You can use it to sign up for Part B if your Initial Enrollment Period is over and you don't qualify for a Special Enrollment Period.

Your coverage starts the month after you sign up, and you might pay a monthly late enrollment penalty.

If you have coverage through your job or your spouse's job, a Special Enrollment Period lets you sign up for Part B without the late penalty.

That window ends 8 months after the job-based coverage or the job ends, whichever happens first.

If you sign up while you or your spouse is still working, you can ask to delay your Part B start date by up to 3 months.

This Special Enrollment Period doesn't apply while you're still in your Initial Enrollment Period.

Plan changes have Special Enrollment Periods too.

They may open when you move, change or lose your coverage, or begin receiving Medicaid or Extra Help with drug costs.

How to Join or Switch a Medicare Plan

Once you pick a Medicare plan, there are three ways to join it.

You can select Enroll for the plan at Medicare.gov, contact the plan, or call 1-800-MEDICARE (1-800-633-4227).

Check that the plan covers your prescriptions and that your doctors and pharmacies are in its network.

You need both Part A and Part B to join a Medicare Advantage Plan, but only one of them to join a drug plan.

You also generally must live in the plan's service area.

Have your Medicare Number and your Part A and/or Part B coverage start dates ready, since you can find that information on your Medicare card.

Free Medicare Help in Tennessee

Tennessee's State Health Insurance Assistance Program (TN SHIP) describes itself as a federally funded program offering free, unbiased counseling to Medicare-eligible Tennesseans, their families and caregivers.

Whether you're new to Medicare or a longtime member, its trained counselors can help with your Medicare questions.

You can reach TN SHIP at 1-877-801-0044.

If you're turning 65 with a Marketplace plan, you'll need to disenroll from it once you're eligible for Medicare.

Typically, a Marketplace plan won't work with Medicare.

FAQ

There are three enrollment periods for signing up for Part A and Part B.

They're the Initial Enrollment Period, a Special Enrollment Period for people with job-based coverage, and the General Enrollment Period.

When does Medicare open enrollment end in Tennessee?

Medicare open enrollment ends December 7.

Your request counts only if the plan gets it by that date.

When do open enrollment changes take effect?

Changes you make during open enrollment take effect January 1 of the following year.

That start date applies to Medicare Advantage and drug plan changes.

Can you change Medicare plans after December 7?

Sometimes, since people in a Medicare Advantage Plan can switch plans or return to Original Medicare from January 1 to March 31.

A Special Enrollment Period can also open for situations like moving or losing coverage.

What happens if you sign up for Part B late?

Waiting adds an extra 10% to your Part B premium for every full year you could have signed up.

You generally skip that penalty if you qualify for a Special Enrollment Period.

Where can Tennesseans get free help comparing Medicare plans?