Best Medicare Part D Prescription Drug Plans (2026)

We evaluated Medicare Part D plans based on five criteria: CMS star rating, formulary breadth, pharmacy network size, total annual cost (premiums plus out-of-pocket), and plan stability. Each plan below serves a different type of beneficiary, from budget-conscious enrollees who primarily take generics to people on expensive specialty medications who benefit from a $0-deductible plan.

Best for low out-of-pocket costs: Humana Walmart Value Rx. Best for low premiums: Wellcare Value Script. Best for large formulary and low deductible: AARP MedicareRx Preferred. Best for generic drugs: HealthSpring Secure Rx. Best for pharmacy network: Blue Cross MedicareRx Plus.

Humana Walmart Value Rx stands out for offering $0 copays on both Tier 1 and Tier 2 drugs at preferred pharmacies, a benefit no other major national plan matches. The plan is available in 27+ states with $0 monthly premiums in many areas, making it one of the most accessible low-cost options for 2026.

The trade-off is a higher deductible (up to $615 in some regions) and coinsurance on brand-name and specialty drugs. But for beneficiaries who primarily take generics and use Walmart, Sam's Club, or other preferred pharmacies, total annual costs can be among the lowest available. Humana also offers a Premier plan with a $0 deductible for those willing to pay a higher monthly premium.

Wellcare Value Script consistently offers some of the lowest monthly premiums of any national Part D plan. For beneficiaries on a tight budget who want basic drug coverage without a large monthly expense, Wellcare is hard to beat on price. The plan also earns strong CMS quality ratings, meaning low cost does not come at the expense of plan performance.

The main limitation is the full $615 deductible in most areas and coinsurance on brand-name drugs that can add up for beneficiaries with complex medication regimens. Wellcare works best for people who take a small number of generic medications and want to minimize their fixed monthly costs.

AARP MedicareRx Preferred from UnitedHealthcare offers the largest formulary among major national Part D plans, a $0 deductible, and availability in all 50 states. For beneficiaries who take multiple medications, including brand-name drugs, the combination of broad coverage and no deductible means you start getting plan benefits from day one without paying $615 out of pocket first.

The premium is higher than budget options ($45-$95/month depending on region), but for people with expensive or complex medication needs, the total annual cost (premium + copays) is often lower than a cheap plan with a high deductible and limited formulary. The plan also waives the deductible for Tier 1 and Tier 2 drugs, so generics are covered immediately.

HealthSpring (formerly Cigna) Secure Rx plans offer some of the lowest out-of-pocket costs on Tier 1 and Tier 2 generic drugs. If your medication list is primarily generics, HealthSpring can deliver lower total annual costs than competitors even if the premium is not the absolute cheapest. The Extra Rx plan waives the deductible entirely for Tier 1 and Tier 2 drugs.

HealthSpring offers $0-premium plans in select states, making it a strong contender for beneficiaries in those regions. The main drawback is below-average CMS quality ratings in 2026 and higher costs on brand-name and specialty medications compared to plans like AARP MedicareRx Preferred.

Starting in 2025, Medicare Part D includes a hard cap on annual out-of-pocket drug spending. The cap started at $2,000 in 2025 and rose to $2,100 for 2026. The threshold is indexed annually and adjusts each plan year. Once your total out-of-pocket spending (deductible + copays + coinsurance) reaches $2,100, you pay $0 for all covered drugs for the remainder of the year.

This eliminates the old catastrophic coverage phase where beneficiaries still paid 5% of drug costs indefinitely. The cap applies regardless of which Part D plan you choose. The Medicare Prescription Payment Plan also lets you spread your out-of-pocket costs into equal monthly installments rather than paying large amounts when you fill expensive prescriptions.

Start by listing every prescription you take, including dosage and quantity. Enter your medications into the Medicare Plan Finder along with your preferred pharmacies. The tool calculates your estimated total annual cost (premiums + deductible + copays) for every plan available in your ZIP code.

Compare the top 3-5 plans by total annual cost, not just monthly premium. A $0 premium plan with a $615 deductible and high copays may cost more annually than a $40/month plan with $0 deductible and lower copays. Also check whether your pharmacy is preferred (lower copays) or standard (higher copays), and whether any of your drugs require prior authorization or step therapy.

If you have a Medigap plan, your only option for drug coverage is a stand-alone PDP. You cannot have both a Medigap plan and a Medicare Advantage plan. If you have Medicare Advantage with drug coverage (MA-PD), your medical and drug benefits are bundled together.

You can change your Part D plan during Medicare Open Enrollment (October 15 - December 7) for coverage starting January 1. If you have Medicare Advantage, you get an additional window from January 1 - March 31 to switch to a different MA plan or return to Original Medicare with a stand-alone PDP.

Review your plan every year because formularies, premiums, and pharmacy networks change annually. Plans can drop drugs, add prior authorization requirements, or move drugs to higher cost tiers from one year to the next. Your Annual Notice of Change (ANOC) arrives each September and details what is changing for the following year.

If you go 63 or more consecutive days without creditable drug coverage and later enroll in Part D, you will pay a late enrollment penalty of 1% of the $38.99 national base beneficiary premium for every month you were without coverage. This penalty is permanent and added to your monthly premium for as long as you have Part D.