What can I change during Medicare Open Enrollment?

You can join, switch, or drop a Medicare Advantage Plan (with or without drug coverage), join, switch, or drop a Medicare drug plan (Part D), switch to Original Medicare, or keep your current coverage. If you keep your current plan, coverage continues automatically.

When do Open Enrollment changes take effect?

New health or drug plan coverage chosen during Open Enrollment generally starts January 1 of the next year (2027 for the 2026 Open Enrollment window). Benefit and cost changes for a plan you keep also start January 1.

What should I do before October 15?

Starting around October 1, review your plan’s Annual Notice of Change and other notices about next-year costs and benefits. Then compare plans at Medicare.gov/plan-compare. Official help is available at 1-800-MEDICARE and through your State Health Insurance Assistance Program (SHIP).

Can I change Medicare Advantage after January 1?

If you are in a Medicare Advantage Plan, Medicare Advantage Open Enrollment runs January 1 through March 31. In that window you can switch to a different Medicare Advantage Plan (with or without drug coverage) or switch to Original Medicare with the option to join a separate drug plan. Changes are generally effective the first day of the month after the plan gets your enrollment form.

Medicare Open Enrollment 2026 — Oct 15 to Dec 7

Q: When is Medicare Open Enrollment in 2026?

October 15 through December 7. Changes you make are generally effective January 1, 2027. The plan must receive your enrollment request by December 7.

Q: What happens to Medigap if I join a Medicare Advantage Plan?

If you already have Medicare Supplement Insurance (Medigap) and join a Medicare Advantage Plan, you might decide to drop Medigap. You may not be able to get the same Medigap policy back later, depending on your state’s Medigap enrollment rules and your situation. Confirm with official Medicare sources before you switch.

Medicare Open Enrollment runs October 15 – December 7 each year. It is the main window to review Medicare health and drug coverage and decide whether to make changes for the next calendar year. Changes you elect during this window are generally effective January 1, 2027. The plan must get your enrollment request by December 7.

Official sources: Medicare.gov Open Enrollment and CMS publication 11220 — Your Yearly Medicare Review.

This guide is a date-and-process snapshot for fall 2026 — what you can change, how to prepare, where to get unbiased help, and how Medicare decisions sit next to nearby Finance Maxx tax and retirement tools. It does not list 2027 Part B premiums, IRMAA brackets, or the SSA COLA (those figures are announced separately).

Key dates (fall 2026 → early 2027)

Date	What happens
October 1	Get ready. Review Annual Notice of Change and other plan notices for next-year costs and benefits; start comparing at Medicare.gov/plan-compare.
October 15	Open Enrollment begins. You can join, switch, or drop a Medicare Advantage Plan or Medicare drug plan, or switch to Original Medicare.
December 7	Open Enrollment ends. In most cases this is the last day to change Medicare coverage for next year; the plan must receive your enrollment form by this date.
January 1	New coverage begins (or current coverage continues with any new-year benefit and cost changes).
January 1 – March 31	Medicare Advantage Open Enrollment Period (for people already in a Medicare Advantage Plan): switch to another MA plan or to Original Medicare (with optional Part D). Effective the first of the month after the plan gets your form.

Separately, HealthCare.gov Marketplace open enrollment for 2027 coverage typically begins November 1. That is a different program from Medicare Open Enrollment; use HealthCare.gov if you are shopping Marketplace plans, not Medicare.

What you can do during Open Enrollment

During Open Enrollment, options depend on the coverage you have now. In general you can:

Join, switch, or drop a Medicare Advantage Plan (Part C), with or without drug coverage (or add or drop drug coverage on an MA plan)
Join, switch, or drop a Medicare drug plan (Part D)
Switch how you get coverage — for example, leave Medicare Advantage and return to Original Medicare (Part A and Part B), often with a separate Part D plan and possibly Medigap
Keep your current coverage — if you have reviewed options and are satisfied, you do not need to do anything; coverage continues automatically

Two main ways to get Medicare (from CMS 11220):

Original Medicare — Part A (Hospital) and Part B (Medical); optional separate Part D drug plan; optional Medigap from a private insurer to help with Original Medicare cost-sharing
Medicare Advantage (Part C) — Medicare-approved plans from private companies that bundle Part A, Part B, and usually Part D

Prepare: Annual Notice of Change, compare, get help

Read your Annual Notice of Change (ANOC) and other plan mail. Costs, benefits, networks, and formularies can change each year. CMS 11220 points you to this review starting around October 1.
Compare plans at Medicare.gov/plan-compare (or the latest Medicare & You handbook). Plan Compare can estimate out-of-pocket costs, show quality ratings, check preferred pharmacies and drugs, and search whether your doctors are in network.
Enroll by selecting “Enroll” on Plan Compare, contacting the plan, or mailing a paper form. The plan must receive the enrollment by December 7.
Use official help, not sales mail alone:
- 1-800-MEDICARE (1-800-633-4227); TTY 1-877-486-2048 — 24 hours, including weekends
- State Health Insurance Assistance Program (SHIP) — unbiased counseling; find your local number at shiphelp.org
Cost help programs (if income/resources are limited): Extra Help for Part D (apply via SSA.gov/extrahelp) and Medicare Savings Programs — start at Medicare.gov basics — help with costs.

Around Open Enrollment you may get a lot of marketing mail. Medicare.gov, Medicare & You, and 1-800-MEDICARE are the official unbiased sources.

Medigap caution if you leave Original Medicare for Advantage

If you already have Medicare Supplement Insurance (Medigap) and join a Medicare Advantage Plan, you might decide to drop Medigap. You may not be able to get the same Medigap policy back later, depending on your state’s Medigap enrollment rules and your situation (CMS 11220). If you switch from Advantage back to Original Medicare, Medigap timing and guaranteed-issue rights are limited — confirm on Medicare.gov before you drop anything.

Money context on Finance Maxx (no invented 2027 premiums)

Medicare premiums and IRMAA (income-related monthly adjustment amounts) track taxable income over time. This site does not publish unverified 2027 Part B or IRMAA figures. Use nearby tools for taxable-income and cash-flow context only:

Enhanced senior deduction — temporary Schedule 1-A Part V amount (up to $6,000 per qualifying person) for age-65+ filers; useful when sketching taxable income beside Medicare costs
Federal tax calculator — rough bracket / taxable-income sketch (not IRMAA software)
2027 HSA contribution limits — fall open-enrollment HSA ceilings; confirm Publication 969 — Medicare enrollment generally ends HSA eligibility (you generally cannot contribute once enrolled in Medicare)
2026 401(k) & IRA contribution limits — parallel fall decisions on workplace and IRA contributions that compete for the same cash

Enhanced senior deduction — $6,000 Schedule 1-A Part V for age 65+
Federal tax calculator — taxable-income / bracket sketch
How this federal tax estimate is built — what the calculator models
2027 HSA contribution limits — next-year HSA ceilings; Medicare and HSA eligibility
2026 401(k) & IRA contribution limits — elective deferral and IRA ceilings for fall elections
HSA contribution limits and catch-up — eligibility rules including Medicare note

What this does not do

It is not personalized Medicare, Medigap, or plan-selection advice.
It does not list 2027 Part B premiums, IRMAA brackets, plan bids, or the SSA COLA (not used as facts here until officially published).
It is not a substitute for Medicare.gov, CMS 11220, your Annual Notice of Change, or 1-800-MEDICARE / SHIP counseling.
It does not enroll you in a plan or check network / formulary fit for your doctors and drugs.
Educational only — not insurance, tax, benefits, or legal advice.

FAQ

When is Medicare Open Enrollment?

October 15 – December 7. Changes are generally effective January 1 of the next year; the plan must get your enrollment by December 7 (Medicare.gov).

What can I change?

Join, switch, or drop a Medicare Advantage Plan or Part D plan; switch to Original Medicare; or keep current coverage (auto-continues).

When should I start reviewing?

Around October 1, read your Annual Notice of Change, then compare at Medicare.gov/plan-compare (CMS 11220).

Is there another chance after January 1?

If you are in a Medicare Advantage Plan, January 1 – March 31 is the Medicare Advantage Open Enrollment Period for switching MA plans or returning to Original Medicare (optional Part D).

What about Medigap if I join Advantage?

You may drop Medigap and might not get the same policy back later. Confirm state rules and Medicare.gov before switching (CMS 11220).

Does Medicare enrollment affect HSA contributions?

Generally yes — confirm Publication 969. Once you are enrolled in Medicare, you are typically no longer eligible to contribute to an HSA. Existing HSA funds may still be usable for qualified medical expenses under IRS rules; this page does not replace Pub 969.

Try it yourself

Open Medicare.gov Open Enrollment and download CMS 11220.
Find your plan’s Annual Notice of Change and note premium, deductible, drug, and network changes for 2027.
Run Medicare.gov/plan-compare with your drugs, pharmacies, and doctors.
If income/resources are tight, check Extra Help and Medicare Savings Programs via Medicare.gov help with costs.
For taxable-income context only, open the federal tax calculator and enhanced senior deduction; for competing fall cash decisions, see 2026 401(k) & IRA limits and 2027 HSA limits.
Enroll only through official channels so the plan receives your request by December 7.