Medicare Open Enrollment 2026: Key Part D and Advantage Changes

If you are a Medicare beneficiary heading into 2026, this is one of the most consequential years for your drug coverage in the program's history. The Inflation Reduction Act's landmark $2,000 annual out-of-pocket cap on Medicare Part D prescription drug costs takes full effect in 2026, replacing a system that previously had no ceiling on what you could spend on medications in a single year. For the roughly 50 million Americans enrolled in Part D — either through a standalone Prescription Drug Plan or a Medicare Advantage plan with drug coverage — this change can fundamentally alter how you budget for your health care.

Under the old structure, Part D had four distinct phases: a deductible phase, an initial coverage phase, a coverage gap (the so-called 'donut hole'), and a catastrophic phase. In 2025, the catastrophic phase required beneficiaries to pay 5% of drug costs with no cap. Starting in 2026, once you have spent $2,000 out of pocket on covered drugs, your cost-sharing drops to zero for the rest of the calendar year. That means someone managing multiple expensive medications — say, a cancer drug running $800 a month or a specialty biologic for rheumatoid arthritis — may hit that cap relatively early in the year and pay nothing for the remainder. For beneficiaries who previously faced $5,000, $8,000, or even higher annual drug bills, this is a meaningful financial protection.

However, the cap does not mean your costs automatically go down from day one. The deductible for Part D in 2026 can be as high as $590 — up from $545 in 2025 — and many plans charge that full amount before coverage kicks in. Your copays and coinsurance during the initial coverage phase still apply until you reach the $2,000 threshold. What counts toward the cap includes your deductible, copays, and coinsurance — but not your monthly premium. So if your plan has a $35 monthly premium, that $420 per year does not count toward your $2,000 limit. Understanding this distinction matters when you are comparing plans during enrollment.

Medicare Advantage plans — the private insurance alternative to Original Medicare that now covers more than half of all Medicare beneficiaries — are also seeing significant changes in 2026. Insurers have been recalibrating their offerings in response to higher-than-expected medical costs in recent years, and many plans have adjusted their premiums, cost-sharing structures, and supplemental benefits. According to CMS data, the average Medicare Advantage plan premium in 2026 remains relatively low, but the variation between plans in the same county can be dramatic — from $0 per month to well over $100. A $0-premium plan is not necessarily the best value if its copays for specialist visits, hospital stays, or outpatient procedures are substantially higher than a plan with a modest monthly premium.

One of the most important numbers to focus on when comparing Medicare Advantage plans is the Maximum Out-of-Pocket (MOOP) limit. In 2026, CMS set the MOOP ceiling for Medicare Advantage at $9,350 for in-network services and $14,000 for combined in-network and out-of-network costs. Individual plans can set their MOOP lower than these ceilings, and many do. If you are comparing two plans — one with a $0 premium and a $7,500 MOOP versus one with a $45 monthly premium and a $4,500 MOOP — the second plan may cost you less in a year where you need significant medical care, even though it costs $540 more in premiums. Running these numbers for your specific health situation is essential, not optional.

Supplemental benefits in Medicare Advantage — things like dental, vision, hearing, fitness memberships, and over-the-counter allowances — have been a major selling point for these plans, but 2026 has seen some insurers scale back certain extras as they manage costs. Some plans that previously offered generous dental allowances of $2,000 or more per year have reduced those to $1,000 or eliminated coverage for major services like crowns and dentures. If you enrolled in a Medicare Advantage plan specifically because of its dental or vision benefits, you should verify that those benefits remain intact for 2026 — do not assume your plan's extras are the same as last year. Plans are required to send you an Annual Notice of Change (ANOC) each September, and reading that document carefully is the single most important thing you can do before the AEP begins on October 15.

For beneficiaries who take multiple brand-name or specialty drugs, the Medicare Prescription Payment Plan — also called the smoothing program — is available in 2026. This voluntary program allows you to spread your out-of-pocket drug costs across monthly installments throughout the year rather than paying large lump sums at the pharmacy. If you pick up a specialty medication in January that costs you $600 out of pocket, instead of paying that all at once, you can have it billed in smaller amounts over the remaining months of the year. You must opt into this program through your Part D plan or Medicare Advantage plan; it is not automatic. Contact your plan directly or visit Medicare.gov to enroll.

If you are currently in Original Medicare with a standalone Part D plan and a Medigap (Medicare Supplement) policy, the 2026 changes affect you differently than Medicare Advantage enrollees. Your Medigap policy covers most of your cost-sharing under Parts A and B, but it does not cover Part D drug costs. The new $2,000 cap applies to your standalone Part D plan, so you still benefit from that protection. Medigap plans do not change their core benefits annually the way Medicare Advantage plans do, but premiums can increase, and if you are considering switching Medigap plans, be aware that in most states you can be subject to medical underwriting outside of guaranteed issue periods. The birthday rule — which allows you to switch Medigap plans without medical underwriting during a 30-day window around your birthday — applies in California, Idaho, Illinois, Kentucky, Louisiana, Maine, Maryland, Missouri, Nevada, New Jersey, New York, Oklahoma, and Oregon.

The Annual Enrollment Period runs from October 15 through December 7 each year, and any changes you make take effect January 1. During this window, you can switch from Original Medicare to Medicare Advantage, switch between Medicare Advantage plans, switch from Medicare Advantage back to Original Medicare, join or switch standalone Part D plans, or drop Part D coverage entirely (though dropping coverage without other creditable coverage can result in a late enrollment penalty later). There is also the Medicare Advantage Open Enrollment Period from January 1 through March 31, during which you can make one switch if you are already enrolled in a Medicare Advantage plan — but you cannot use this window to switch from Original Medicare to Medicare Advantage. Use the Medicare Plan Finder tool at Medicare.gov to compare plans available in your ZIP code, enter your specific medications, and see your estimated annual costs side by side.