When Is Medicare Open Enrollment, and What Should I Review?
What Exactly Is Medicare Open Enrollment?
Every year, Medicare gives you a window to make changes to your health coverage. This window, officially called the Annual Enrollment Period, runs from October 15 through December 7. Any changes you make take effect on January 1 of the following year.
During this period you can switch from Original Medicare to a Medicare Advantage plan (or vice versa), change your Medicare Advantage plan, or join, switch, or drop a Part D prescription drug plan. Outside of this window, your options are generally locked unless you qualify for a Special Enrollment Period triggered by specific life events like moving or losing employer coverage.
Why Should I Review My Coverage Every Year?
Here is the honest truth: skipping your annual review is one of the most common and costly Medicare mistakes. Plans change every year. Premiums go up or down, pharmacies leave networks, and drug formularies shift. A plan that saved you money last year could cost you hundreds more next year, even if you do nothing different.
By law, your plan must mail you an Annual Notice of Change (ANOC) by September 30. This document spells out what is changing for the upcoming plan year. Do not toss it in a drawer. It is your starting point for deciding whether to stay or switch.
What Should I Actually Review? A Practical Checklist
1. Your Prescriptions
Pull out a current list of every medication you take, including dosages. Then check whether each drug is still on your plan's formulary (the list of covered medications) and what tier it falls on. A drug moving from Tier 2 to Tier 3 can mean a significant jump in your copay. You can look up your drugs using the Medicare Plan Finder tool at Medicare.gov.
2. Your Doctors and Specialists
If you are in a Medicare Advantage plan or considering one, confirm that your primary care doctor, specialists, and preferred hospital are in the plan's network. Networks can change from year to year. In the Oklahoma City metro, some plans have broad networks that include major health systems, while others are more limited. Always verify directly with the plan.
3. Your Total Costs, Not Just the Premium
A low monthly premium can be tempting, but it does not tell the full story. Look at the complete picture: the premium, annual deductible, copays and coinsurance for services you actually use, and the out-of-pocket maximum. If you visit specialists frequently or have a chronic condition, a plan with a slightly higher premium but lower copays could save you real money over the year.
4. Prescription Drug Coverage (Part D) Details
Even if you are happy with your medical coverage, review your Part D plan separately. Check the plan's preferred pharmacy list. Using a preferred pharmacy versus a non-preferred one can cut your drug costs significantly. In Oklahoma, many retail chains and independent pharmacies participate, but coverage varies by plan.
5. Extra Benefits in Medicare Advantage Plans
Many Medicare Advantage plans offer extras like dental, vision, hearing, fitness programs, or even grocery allowances. These benefits are real, but they vary widely between plans and can change annually. Make sure the extras you rely on are still included and offered at the same level.
What About Medigap (Medicare Supplement) Policies?
If you are on Original Medicare, you may have a Medigap policy that helps cover costs like deductibles and coinsurance. Important note: Open Enrollment is not the time to change Medigap policies. Medigap has its own enrollment rules. Your best opportunity for Medigap is your six-month Medigap Open Enrollment Period, which starts the month you turn 65 and are enrolled in Part B. Outside that window, insurers in most states (including Oklahoma) can use medical underwriting, meaning they can deny you or charge more based on your health.
If you are considering switching from a Medicare Advantage plan back to Original Medicare during the Annual Enrollment Period and want to add a Medigap policy, talk to a counselor first. Your options may depend on your health history and state rules.
Free Help Is Available, Especially in Oklahoma
You do not have to figure this out alone, and you should not pay anyone to help you enroll in Medicare. Oklahoma's State Health Insurance Assistance Program (SHIP) provides free, unbiased counseling from trained volunteers who do not sell insurance. They can help you compare plans, understand your ANOC, and make sure you are not overpaying.
You can reach Oklahoma SHIP through the Oklahoma Insurance Department or by calling the national Eldercare Locator at 1-800-677-1116. Many local Area Agencies on Aging across the Oklahoma City metro and statewide host Medicare enrollment events each October and November, offering one-on-one help at no cost.
If you think you might qualify for financial assistance, ask about Extra Help (the Low-Income Subsidy for Part D) and Medicare Savings Programs that can help pay premiums, deductibles, and copays. You can apply for Extra Help any time of year through the Social Security Administration at ssa.gov or by calling 1-800-772-1213.
Key Dates to Remember
- September 30: Deadline for your plan to send the Annual Notice of Change
- October 15 to December 7: Medicare Annual Enrollment Period (Open Enrollment)
- January 1: New coverage begins
- January 1 to March 31: Medicare Advantage Open Enrollment Period (for current Advantage enrollees only)
A Few Common Mistakes to Avoid
- Ignoring the ANOC mailing. Changes buried in that document can affect your wallet and your care.
- Choosing a plan based on premium alone. Total cost of care matters far more than the monthly premium.
- Assuming your doctors are still in network. Verify every year, not just the first year.
- Waiting until December 7 to start researching. Give yourself time. Plan comparison takes a few hours but can save thousands.
- Paying a broker without understanding they earn commissions. Free, unbiased help through SHIP exists for a reason.
Medicare decisions affect your health and your finances for the entire year ahead. Taking a couple of hours each fall to review your coverage is one of the highest-return investments of time you can make. If you want help navigating your options or connecting with a trusted local advisor who understands Medicare in Oklahoma and beyond, visit Second Half 365 to find a verified local expert who can walk through your choices with you, at no cost and no pressure.
Frequently Asked Questions
When is Medicare Open Enrollment for 2025?
Medicare Open Enrollment (also called the Annual Enrollment Period) runs from October 15 through December 7, 2025. Changes you make during this window take effect on January 1, 2026. Missing this deadline generally means waiting until the next year unless you qualify for a Special Enrollment Period.
Can I switch from Medicare Advantage back to Original Medicare during Open Enrollment?
Yes. During the Annual Enrollment Period (October 15 to December 7), you can switch from a Medicare Advantage plan back to Original Medicare, or move between Advantage plans. If you switch to Original Medicare, you may also want to enroll in a standalone Part D drug plan and consider a Medigap (supplement) policy, though Medigap acceptance may depend on your state's rules and your health history.
What is the Medicare Advantage Open Enrollment Period, and how is it different?
The Medicare Advantage Open Enrollment Period runs January 1 through March 31 each year. It is only for people already enrolled in a Medicare Advantage plan. During this window you can switch to a different Advantage plan or drop your Advantage plan and return to Original Medicare with a Part D plan. You cannot use this period to go from Original Medicare into an Advantage plan.
Where can I get free Medicare counseling in Oklahoma?
Oklahoma's State Health Insurance Assistance Program (SHIP) offers free, unbiased Medicare counseling. You can reach them by calling the Eldercare Locator at 1-800-677-1116 or by contacting the Oklahoma Insurance Department directly. Local Area Agencies on Aging across the state, including those serving the Oklahoma City metro, also host enrollment events and one-on-one counseling sessions each fall.
Will my Medicare Part D drug plan automatically change its formulary?
Yes, Part D plans can change their formulary (the list of covered drugs), copay tiers, and preferred pharmacies every plan year. Your plan is required to send you an Annual Notice of Change (ANOC) by September 30. Review it carefully because a medication you currently take could move to a higher cost tier or be dropped from coverage entirely.
What does Extra Help (Low-Income Subsidy) cover for Medicare Part D?
Extra Help, also called the Low-Income Subsidy, is a federal program that helps pay Part D premiums, deductibles, and copayments. In 2025, individuals with limited income and resources may qualify. You can apply through the Social Security Administration at ssa.gov or by calling 1-800-772-1213. There is no enrollment period for Extra Help; you can apply any time of year.
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