Medicare’s open enrollment period has been in full swing since mid-October. At this point, you only have a couple more weeks to make changes to your Medicare coverage.

If you’re switching from a Medicare Advantage plan to original Medicare for 2025, you’ll need to choose a Part D plan for prescription drug coverage. And if you’re unhappy with your current Part D plan, you may be interested in putting a different one in place for the new year.

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In the course of choosing your Part D coverage, you’ll want to be mindful of the costs you’ll be facing. Those will ultimately hinge on the plan you select and the exact prescriptions you take.

But there are certain general costs it’s helpful to know about as a Part D enrollee. And there are also certain income thresholds to keep in mind, as they could affect what you pay for drug coverage. Here are four important Medicare Part D numbers to know going into 2025.

1. $590

Not all Part D drug plans impose a deductible. But if your plan has one, the maximum deductible a Part D plan can charge in 2025 is $590.

2. $2,000

Even with Part D drug coverage, it’s common to have to spend money on copays. The good news is that beginning in 2025, Medicare Part D out-of-pocket drug costs will be capped at $2,000. This new rule may not only spell relief, but also help you better work prescription costs into your budget.

3. $106,000

The premium you pay for Part D coverage depends on the specific plan you choose. Unlike Part B, there’s no standard monthly premium.

But higher earners are subject to surcharges on their Part D premiums — known as income-related monthly adjustment amounts, or IRMAAs. If you’re a single tax-filer with a modified adjusted gross income (MAGI) of $106,000 or less, you won’t face an IRMAA in 2025. But once your MAGI goes above $106,000, you’ll pay more for whatever Part D plan you choose. And the higher your income, the larger an IRMAA you might get stuck with.

4. $212,000

The income thresholds for Part D IRMAAs are different for married couples than singles. If you’re a married couple filing a joint tax return, a MAGI of $212,000 or less means you won’t face a Part D IRMAA in 2025. But beyond $212,000, you’re looking at a surcharge.

Know what costs to expect

Chances are, Medicare Part D and its associated costs will eat up a fair chunk of your budget in 2025. So it’s important to know what to expect from Part D, in general.

What’s equally important, though, is making sure you understand the ins and outs of your drug plan. If you’re switching Part D coverage for 2025, spend the coming weeks reading up on your plan’s rules. That way, you’re less likely to be thrown for a financial loop once the new year arrives, and you’ll be less likely to land in a situation where there’s a delay in getting the medications you rely on.

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