Key Takeaways

• Medicare rules evolve more frequently than many people expect, especially around costs, enrollment periods, and coverage options.

• Staying current on these changes is essential to avoid late penalties, coverage gaps, or unnecessary out-of-pocket costs.

The Assumptions That Don’t Hold Up

You may assume that once you enroll in Medicare, it’s a set-it-and-forget-it program. But the reality is very different. Medicare is a federal program with rules that adjust year to year. While the basic structure remains stable, the fine print shifts, and those details affect your costs and your coverage.

In 2025, the Medicare landscape includes updated premiums, altered income brackets for surcharge thresholds, new out-of-pocket caps for prescription drugs, and changed enrollment expectations for some individuals. These updates reflect efforts to modernize the system, address inflation, and expand access to affordable care. But they also add complexity.

1. Medicare Part B Premiums and Deductibles Keep Rising

If you’re relying on what you heard last year, you may be budgeting incorrectly. In 2025, the standard Medicare Part B premium is $185 per month. That’s up from $174.70 in 2024. Similarly, the annual Part B deductible has increased to $257.

This change is not unusual. Medicare Part B costs have risen consistently over the years, and many beneficiaries are surprised by how quickly those monthly figures add up. Individuals with higher incomes will also see larger surcharges based on updated Income-Related Monthly Adjustment Amount (IRMAA) brackets.

2. The Part D Prescription Drug Landscape Just Changed

The Part D structure in 2025 has eliminated the coverage gap, commonly called the “donut hole.” Previously, you may have expected to pay more after reaching a certain spending threshold. That model is gone.

Here’s what the new system looks like:

• Deductible Phase: You pay up to $590 out of pocket.

• Initial Coverage Phase: You pay a share (copayment or coinsurance) until you reach $2,000 in out-of-pocket costs.

• Catastrophic Phase: Once you hit the $2,000 cap, your Part D plan pays 100% of covered drug costs for the rest of the year.

This change simplifies budgeting and improves predictability, but if you still think the donut hole exists, you may be confused about your current responsibilities.

3. The Income Brackets That Trigger IRMAA Are Updated Annually

You may think you don’t earn enough to face a Medicare premium surcharge, but the thresholds for IRMAA change annually. For 2025, these surcharges apply to individuals earning over $106,000 and married couples filing jointly earning over $212,000. That’s based on your Modified Adjusted Gross Income from 2023.

Failing to account for a temporary increase in income—such as a one-time sale or IRA withdrawal—can push you into IRMAA territory and cost you hundreds more in premiums each month for Parts B and D.

4. Open Enrollment Is Consistent, But Rules Within It Shift

The Medicare Open Enrollment period occurs every year from October 15 through December 7. This window is familiar, but what changes within it are the plans themselves.

Each year, plan options may be added, dropped, or changed significantly. For 2025, some supplemental benefits have become less common, including transportation and over-the-counter item allowances. Many plans have also adjusted their provider networks and formularies. If you don’t review your plan annually, you could be left with fewer benefits or higher costs without realizing it.

5. The Medicare Advantage Landscape Is Never Static

While Medicare Advantage (Part C) plans may look appealing for their extra perks, those perks are subject to annual revision. For example, the number of plans offering certain supplemental benefits has declined in 2025:

• Over-the-counter allowances have dropped from 85% of plans in 2024 to 73% in 2025.

• Transportation benefits have decreased from 36% to 30%.

That means if you enrolled last year expecting those features, you may be surprised to find them missing now. It’s a reminder that what was true about a plan even a year ago may no longer be accurate.

6. New Notifications Are Meant to Help—If You Read Them

A new requirement in 2025 is the Mid-Year Enrollee Notification of Unused Supplemental Benefits. If you’re enrolled in a Medicare Advantage plan, you will receive a personalized notice between June 30 and July 31. It will list the supplemental benefits you haven’t used yet.

While helpful, this tool only works if you review and act on it. Otherwise, you may miss out on valuable services, like vision care, dental cleanings, or fitness programs that you assumed were no longer available.

7. Enrollment Rules Vary More Than People Expect

Medicare enrollment sounds simple: you turn 65 and you sign up. But there are multiple scenarios that complicate that idea:

• If you’re still working at 65 and have creditable coverage, you may delay Part B.

• If you don’t qualify for premium-free Part A, you may choose to delay enrolling entirely.

• If you miss your Initial Enrollment Period, you must wait for the General Enrollment Period from January 1 to March 31, and coverage begins July 1.

• If you retire mid-year, you may qualify for a Special Enrollment Period that gives you up to eight months to enroll in Part B without penalty.

If you’re going by rules you heard five years ago, you may overlook one of these scenarios and end up facing penalties or late enrollment delays.

8. Coordination with Other Coverage Keeps Shifting

Many people misunderstand how Medicare coordinates with other insurance. In 2025, new changes in public programs, such as the PSHB (Postal Service Health Benefits) system, require Medicare-eligible annuitants to enroll in Medicare Part B to maintain certain benefits. These types of integrations are increasing across retiree and employer-sponsored plans.

If you have FEHB, PSHB, TRICARE, or retiree coverage, it’s essential to confirm whether Medicare enrollment is required, optional, or impacts your benefits in another way.

9. Some Services Are Still Not Covered

Even with all the changes Medicare introduces each year, certain exclusions remain consistent. But assumptions around these services often trip people up. Medicare still does not cover:

• Long-term custodial care

• Routine dental care

• Hearing aids

• Most vision care

While Medicare Advantage plans may offer limited benefits in some of these areas, they are never guaranteed and often subject to change. Believing that “Medicare covers everything” can leave you unprepared for substantial out-of-pocket costs.

10. Penalties Don’t Go Away With Time

One of the most stubborn misconceptions is that if you miss your enrollment window, you can fix it later without consequences. But late enrollment penalties for Part B and Part D are lifelong unless you qualify for an exception.

For every 12-month period you delay Part B without creditable coverage, your premium increases by 10%, permanently. The same applies to Part D with a separate formula. These rules don’t change each year, but the consequences grow more significant over time.

11. Medicare Supplement (Medigap) Enrollment Windows Vary by State

Although Medigap plans are standardized federally, each state has flexibility in how open enrollment and guaranteed issue rights are handled. Some people wrongly believe they can switch Medigap plans anytime. In most cases, after your six-month Medigap Open Enrollment Period (starting the month you are 65 and enrolled in Part B), you may be subject to medical underwriting if you apply later.

A few states offer birthday rules or anniversary windows, but these are not universal. Relying on outdated assumptions about switching Medigap plans can lead to denied coverage or higher rates.

12. The Definitions of “Creditable Coverage” Get Reevaluated

Whether you can delay Part B or Part D without penalty depends on whether your existing coverage is deemed creditable. But what counts as creditable can shift based on updates to plan quality, structure, or costs. A retiree plan that qualified as creditable last year might no longer meet that standard.

Medicare requires your employer or insurer to send you an annual notice regarding creditable coverage, usually by October. If you miss it or ignore it, you could be misinformed about your penalty risk.

Staying Current Matters More Than Ever

In 2025, the pace of Medicare changes remains brisk. From rising costs and shifting thresholds to new communications and updated plan benefits, what you knew even a year ago may no longer apply. Medicare is not a passive program. It requires annual attention and a willingness to adapt.

If you aren’t sure whether the information you have is still accurate, it’s best to verify it now rather than discover the mistake during a medical emergency or at tax time.

Speak With a Professional Before You Miss Something

Every year brings Medicare updates that can affect how you budget, how you access care, and what benefits you can rely on. The sooner you understand what has changed in 2025, the better equipped you are to make informed decisions about your coverage.

If you have questions about what’s changed or how it affects you, get in touch with a licensed agent listed on this website. They can help you confirm current details, explore your options, and avoid costly misunderstandings.