Medicare Open Enrollment Ends Dec. 7—Should You Switch to a Medigap Plan?

Time's running out—Medicare's open enrollment slams shut December 7. The clock is ticking for a critical financial health check.

Medigap's Promise vs. Medicare's Maze

Original Medicare leaves gaps—deductibles, copays, coinsurance. Medigap plans, sold by private insurers, promise to patch those holes. But navigating the switch is a bureaucratic obstacle course with permanent consequences.

Enrollment Windows Are Everything

Miss the December 7 deadline? You're locked out until next year. The best time to buy a Medigap policy is during your six-month Medigap Open Enrollment Period—it starts the month you turn 65 and are enrolled in Part B. After that, insurers can deny coverage or charge more based on health. One wrong move here costs more than a bad crypto trade.

The Cost-Benefit Calculus

Premiums vary wildly by plan, location, and insurer. Plan F and Plan G offer the most comprehensive coverage, but you're trading predictable monthly costs for potential long-term savings on out-of-pocket expenses. It's a hedge against medical volatility—arguably more reliable than most traditional retirement portfolios lately.

Provocative but Balanced Closer

Switching to Medigap isn't for everyone, but ignoring the deadline is a gamble with your financial health. Do the math before December 7 cuts off your options. After all, managing retirement risk shouldn't be more speculative than the markets.

Key Takeaways

• Medicare Supplement (Medigap) plans help you pay for deductibles, copays, coinsurance, and other out-of-pocket expenses not covered by Original Medicare. 
• They’re an alternative to Medicare Advantage (MA) plans, which carry low premiums but unpredictable out-of-pocket expenses. 
• You can switch to Original Medicare and Medigap during the 2026 Medicare open enrollment period, which ends on Dec. 7, 2025.
• Switching to Medigap might require medical underwriting, so if you have pre-existing conditions, you could be denied coverage or required to pay more for a plan.

The Medicare open enrollment period runs until Dec. 7, so there’s still time to make sure you've got the right coverage for 2026. With recent shakeups to the private Medicare Advantage (MA) market—fewer plans and trimmed-down extras—it might be worth considering a switch to Original Medicare with a Medicare Supplement. Just make sure you understand what you'd be gaining—and what you might give up.

Why Consider Switching to a Medicare Supplement (Medigap) Plan

Original Medicare (Part A and Part B) has its upsides. Unlike Medicare Advantage, it doesn't limit you to using a particular provider network. You can get care at almost all U.S. hospitals and doctor offices, and you rarely need prior authorization for medical services or supplies.

Warning

Six states are testing pre-authorization rules for Original Medicare in 2026.

However, also unlike MA plans, Original Medicare doesn’t cap how much you pay for care in a given year. That’s where having a Medicare Supplement (Medigap) plan can be helpful. Medigap, provided by private insurance companies, helps cover deductibles, copays, and other out-of-pocket expenses.  

“It reduces the risk of paying a lot when the cost [of care] is high,” said Dr. William Soliman, founder of WHITE Manna Capital and head of the Accreditation Council for Medical Affairs (ACMA).

It also makes annual health care costs more predictable. With Medicare Supplement plans, you pay a set monthly premium and, in exchange, the insurer will cover a certain percentage—for instance, 100% of your Part B doctor copays—of your other out-of-pocket costs.    

And, while Medigap doesn’t cover common MA benefits, like vision or dental care, some plans will pay for emergency care while traveling abroad.   

As a result, “individuals who tend to gain the most out of Medigap are those who desire predictable health care expenses and do not wish to be bound by network regulations,” said Clayton Eidson, founder and CEO of AZ Health Insurance Agents. “I meet a lot of retirees who like to travel or have to deal with some underlying condition, or they just need to know their budget is stable, and that is what Medigap can provide.”

Why This Matters to Older Adults

If you qualify for Medicare, you can decide between a one-stop-shop Medicare Advantage plan, or Original Medicare with a Medicare Supplement plan to help defray out-of-pocket costs. Choosing one over the other could save you thousands of dollars, depending on your needs. It's crucial to weigh the tradeoffs before deciding on either during open enrollment.

The Medigap Trade-Offs

Medigap plans do have drawbacks. For starters, plan premiums run higher than MA plan premiums, and, in addition to skipping extra benefits, Medigap doesn’t come with prescription drug coverage, so you’ll need to buy a separate Part D policy if you switch over from an MA plan that provides you medication coverage. 

Plus, “the act of leaving Medicare Advantage for Original Medicare and adding a Medigap plan requires some planning,” said Eidson. 

That’s because while you can switch from an MA to a Medicare Supplement plan during open enrollment, you must meet certain criteria to forego medical underwriting and avoid being denied coverage or charged higher prices for pre-existing conditions. 

The criteria include enrolling during the six-month window that starts once you turn 65 and have Medicare Part B. But you’re also eligible for guaranteed-issue Medigap if you joined an MA plan for the first time, have had it for less than a year and want to switch back to Original Medicare, or if your insurer cancels your MA plan. 

“This year, with many Advantage plan carriers leaving markets, those not typically healthy enough to qualify for a Medigap plan are provided a guarantee-issue period,” said Scott R. Maibor, managing director at Senior Benefits Boston. “It may be the only time they will qualify for a Medigap plan if they are not healthy.”

Related Education

Comparing Costs and Coverage

It’s fairly easy to compare one Medicare Supplement plan to another, given that all 10 plan types (A through N) offer standardized benefits. 

The big variables are your quoted monthly premiums and available discounts. For instance, some insurers offer discounts to women, non-smokers, and married couples, while others discount automatic payments or multiple policies. For reference, the average Medigap premiums may range from $32 to $550 per month.

“The rule of thumb is to always compare the Medigap carriers by the plan letter, followed by the price, and last but not least is the rate history of the company,” Eidson said. “Plan G is a Plan G regardless of who is selling it; the real question is how that company maintains its rates and how it treats policyholders.”

Choosing between Medigap and Medicare can prove trickier, but you can determine fit based on the following:  

Consider Medicare Supplement (Medigap) if:

• You anticipate high or unpredictable health care costs.
• You travel frequently or otherwise need flexible networks.
• You qualify for a guaranteed-issue plan.

Consider Medicare Advantage if:

• You want to save on monthly premiums.
• You’re looking for bundled benefits, including vision and dental.
• You’re unhealthy, but don’t qualify for guaranteed-issue coverage.

How to Evaluate and Make a Change

If you’re considering a last-minute switch, take the following steps to pick the best Medicare plan for you. 

• Review your Medicare Annual Notice of Change (ANOC) to ensure you’re aware of all significant changes to your current plan’s pricing, provider network, prescription drug coverage, and supplemental benefits—and whether a change is warranted.
• Compare the out-of-pocket expenses for any plans you're considering. You can use the Medicare Plan Finder to identify your options. Look at all premiums, deductibles, copays, and coinsurance. Remember, Original Medicare and Medigap don't cover prescription drugs. If you want to switch from an MA plan that does, you’ll need to buy (and consider the cost of) a standalone Part D policy.   
• Evaluate your health status. If you have a chronic illness or require frequent, costly treatments, like physical therapy, your deductibles, copays, and coinsurance are likely to add up—and Medicare Supplement premiums could ultimately prove cheaper. For instance, “I had a client tell me she did not want to pay $200 a month for a supplement but is paying an $800 copay three or four times per year for an injection in her back,” Maibor said.  
• Understand your Medigap eligibility. If you’re unhealthy, but need to go through medical underwriting, you might not qualify for a plan or affordable premiums, and you might benefit most from choosing a new MA plan.   
• Contact a licensed Medicare broker or State Health Insurance Assistance Program (SHIP) counselor if you’re having a hard time comparing plans and want outside help. 
• Make all decisions by Dec. 7, 2025. That’s the final day of Medicare open enrollment. Your new selections will take effect on Jan. 1, 2026.