Open enrollment begins on Oct. 15 and runs through Dec. 7, but seven out of ten Medicare beneficiaries probably will not compare their coverage options, if the latest data from the Kaiser Family Foundation is any indication. 

If you are enrolled in traditional Medicare with a Medigap supplemental plan, there is no need to re-evaluate or make changes. But anyone enrolled in a Medicare Advantage or Part D prescription drug plan should do a checkup annually. The terms of your Part D coverage can change from year to year in ways that affect not only your costs, but access to medications. The same is true for Advantage plans that wrap in drug coverage - and the healthcare providers included in these managed care networks also can change.

This fall, there is some good news for seniors enrolled in Medicare for 2023, as some costs are falling. But the plan- shopping process can be complex - and there are pitfalls to avoid.

One pleasant surprise for next year is a falling Part B premium. The standard monthly Part B premium will drop next year by $5.20, to $164.90, and the annual Part B deductible will also decline, by $7, to $226. The very unusual decline is the result of the recent fracas surrounding Aduhelm, the controversial, very expensive drug for treating Alzheimer's Disease, is administered in outpatient settings, so it is covered under Part B. 

The Food and Drug Administration approved Aduhelm in 2021, and - assuming that the drug would be covered - Medicare increased the 2022 Part B premium by a whopping 14.5% to $170.10 per month. But Medicare ultimately decided to limit coverage to certain clinical trials - which meant beneficiaries have been overcharged this year. 

The premium drop next year amounts to a refund of that overcharge.

Seniors can count on adding that $5.20 monthly refund to the hefty 8.7% Social Security cost-of-living adjustment (COLA) for 2023 announced on Thursday. Part B premium hikes often consume a good part of the Social Security COLA - but not in 2023. 

The landmark Inflation Reduction Act phases in changes to Medicare over several years that should help moderate costs. In 2023, vaccines covered under Part D come with no copays or deductibles, which should help with expensive jabs such as the shingles vaccine. 

The IRA also caps the soaring cost of insulin, with a maximum monthly copay for Medicare enrollees of $35 - a godsend for diabetics. However, this improvement comes with one caution for beneficiaries shopping for Part D plans using the Medicare Plan Finder, according to Frederic Riccardi, president of the Medicare Rights Center.

Since the IRA was passed so recently, the insulin copay cap will not be reflected in online descriptions of plan costs. Riccardi recommends running searches for plans by making sure your insulin prescription is included in a plan's list of covered drugs (the formulary), and then omitting insulin from your list of drugs. "So long as a plan does include insulin in its list of covered drugs, you can estimate your costs by adding back in the $35 copay," he said.

CHANGING YOUR BASIC COVERAGE

Open enrollment offers an annual opportunity to switch between traditional Medicare and Advantage. 

Switching out of the traditional program could save you money on upfront premium costs - but the move does come with tradeoffs. These plans incentivize you to use in-network health providers, which may limit your choices.

You also will be jumping through the hoops of paperwork and processes that insurance companies use to manage your care - and sometimes, deny it. A report issued earlier this year by the Office of the Inspector General at the U.S. Department of Health and Human Services noted that Medicare audits of Advantage plans "have highlighted widespread and persistent problems related to inappropriate denials of services and payment." The report found that denials of requests "that meet Medicare coverage rules may prevent or delay beneficiaries from receiving medically necessary care and can burden providers."

You also can leave Advantage for traditional Medicare during the enrollment period. But do this with caution. Seniors who use traditional Medicare should have supplemental coverage, often through a commercial Medigap plan. You are guaranteed access to these policies at the point of initial enrollment in Part B - but after this period, Medigap plans in most states can reject applications or charge higher premiums due to pre-existing conditions, with the exception of four states that protect Medigap applicants beyond that time (New York, Connecticut, Maine and Massachusetts all have some form of guaranteed issue rules for later Medigap enrollment.)

SHOPPING RESOURCES

Start your shopping process by reviewing the Annual Notice of Change letter that comes each autumn from your Medicare prescription drug or Advantage plan provider. The annual notice details any changes in rules for cost-sharing, coverage of specific medications in your current plan, and even whether a specific drug will be covered.

The State Health Insurance Assistance Program network provides free one-on-one assistance in every state. These are federally funded programs staffed by trained volunteers; use this link to find yours.

The Medicare Rights Center offers a free consumer helpline: (800-333-4114.)

When it comes time to enroll, call Medicare to sign up (800-633-4227) and to ensure that your enrollment has been processed.

The opinions expressed here are those of the author, a columnist for Reuters.

(Writing by Mark Miller in Chicago; Editing by Matthew Lewis)

By Mark Miller