Retirees, This Could Be the Biggest Mistake You Make During Medicare's Open Enrollment

You may not think of October as the most important month of the year for retirees. But it's significant for a couple of reasons.

First, October is when the Social Security Administration typically announces a cost-of-living adjustment for the upcoming year. This year, that announcement got delayed by more than a week due to the government shutdown. But at this point, Social Security recipients know to expect a 2.8% raise in 2026.

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Secondly, October is when Medicare's open enrollment period begins. Between Oct. 15 and Dec. 7, Medicare enrollees can make changes to their coverage, including:

• Moving from one Part D drug plan to another
• Switching from one Medicare Advantage plan to another
• Moving from Medicare Advantage to original Medicare
• Signing up for Medicare Advantage for the first time

But as you navigate your Medicare plan choices for 2026, there's a big trap you risk falling into. And it's a mistake you might end up sorely regretting.

Make sure to focus on the big picture

In the course of looking for a new Medicare plan, you may be inclined to compare premiums costs. But premiums are only one piece of the puzzle. And if you base your decision on premium costs alone, you could end up paying a lot more for healthcare than anticipated, not to mention get stuck with subpar benefits.

Your plan's premium represents the amount of money you pay each month for your coverage. But it doesn't represent your total cost.

A number of Medicare Advantage and Part D plans, for example, have a $0 premium. But that doesn't automatically make them the best plan for you.

There are other costs you'll need to look at when choosing a Medicare plan, including:

• Deductibles
• Copays for medication
• Coinsurance
• Out-of-network costs

If you're signing up for a Medicare Advantage plan, also recognize that different plans offer different benefits. It may be that a cheaper plan costs you less, but also covers less. If you end up having to pay for certain services on your own, you could end up spending more money overall next year, despite your plan having a lower premium.

Plus, one known drawback of Medicare Advantage plans is that they limit you to what could be a pretty narrow network of providers. Going outside of your plan's network could mean facing very high costs, or not having your care covered at all.

You may be able to find a Medicare Advantage plan that's cheaper than other choices in your coverage area. But if that plan does not include your preferred providers, you may want to reconsider.

After all, it takes time to build trust with doctors. Are you really willing to give that up to save money?

The answer may be yes depending on your circumstances. The point, however, is to factor your provider network into your decision as well.

Consider all of the details when making your choice

It's natural to compare Medicare plan premium costs during open enrollment and call it a day, but there's a lot more to the story than that. It's important to understand the total costs you're looking at for each coverage option to see which plan is best for you.

And remember, it may be that the plan you have currently is, in fact, the most cost effective. You just won't know until you look around and compare your choices.

The good news is that you still have more than a month left to find yourself a new Medicare plan before open enrollment comes to an end. Give yourself ample time so you're not forced to rush through the process.

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