Medicare Part D Enrollment, Premiums, and Cost Sharing in 2026

The average monthly premium decreased for PDPs in 2026, but the premium for Part D coverage is still substantially higher for PDPs than for MA-PDs

The temporary Part D premium stabilization demonstration for stand-alone PDPs established by the Biden administration in 2024 and renewed for a second year by the Trump administration in 2025 continues to work as intended to help stabilize PDP premiums, with the average monthly PDP premium decreasing 7% between 2025 and 2026, from $39 to $36. This is despite monthly premium increases in some PDPs of up to $50, the maximum increase allowed in 2026 for plans participating in the premium stabilization demonstration.

On average, PDP enrollees continue to pay substantially more each month for their Part D drug coverage than enrollees in MA-PDs. The $36 average monthly PDP premium is more than 4 times higher than the $8 average monthly premium for drug coverage in MA-PDs (weighted by enrollment) (Figure 4). (The total average premium for MA-PDs, including all Medicare-covered benefits, is $15 per month in 2026.) The weighted average MA-PD premium for Part D coverage increased modestly between 2025 and 2026 (up from $7 to $8). (These estimates are based on enrollment in March 2026 and factor in new plans for 2026, plan changes during open enrollment, and new enrollees, and therefore differ from other estimates published in a separate KFF brief, which are based on MedPAC’s projection of average monthly Part D premiums in 2026 using 2025 enrollment and not factoring in new plans, plan switching, or new enrollees.)

The average premium for drug coverage in MA-PDs is heavily weighted by zero-premium plans because MA-PD sponsors can use rebate dollars from Medicare payments to lower or eliminate their Part D premiums. Rebates to Medicare Advantage plans have tripled since 2015 and now exceed $2,600 per year per beneficiary. 

Within the PDP market, average monthly premiums vary by the generosity of Part D coverage offered by a given plan—namely, whether they are basic or enhanced plans, and the amount of the drug deductible. Enhanced Part D plans offer a more generous benefit than basic plans through lower cost sharing, a lower (or no) drug deductible, or better formulary coverage. In 2026, 58% of PDP enrollees (10.8 million) are in enhanced PDPs, and they face an average monthly premium of $39, 27% higher than the average $31 premium faced by the 42% of PDP enrollees (7.8 million) in basic plans. Only 4% of PDP enrollees are in a plan charging zero deductible, but they face an average monthly premium of $127, while the 78% of PDP enrollees in a plan charging the standard $615 deductible face an average monthly premium of $22. Among MA-PD enrollees, there is considerably less variation in monthly premiums by these measures of plan generosity, which reflects both the large share of MA-PD enrollees in zero premium plans (as described below) and the fact that 94% of MA-PD enrollees are in enhanced plans.

Nearly 8 in 10 MA-PD enrollees without low-income subsidies pay no monthly premium for Part D coverage, while around 3 in 10 PDP enrollees pay no premium

Nearly 80% of MA-PD enrollees without low-income subsidies (79% or 14.3 million) pay no monthly premium for Part D coverage in 2026, compared to 28% of PDP enrollees without LIS (4.0 million) (Figure 5). For the average Medicare beneficiary in 2026, 21 out of their 32 MA-PD options charge no premium for drug coverage, while 2 out of their 11 PDP options charge no premium.

Of the 4.0 million non-LIS PDP enrollees paying zero premium, 62% (2.5 million) were enrolled in Wellcare Value Script, which was available for zero premium in 14 out of 34 PDP regions, 10% (0.4 million) in Humana Basic Rx, which was available for zero premium in 21 regions, and another 10% in Humana Value Rx, available for zero premium in 5 regions.

While 79% of non-LIS MA-PD enrollees pay no premium for drug coverage, among the 21% who do, the average monthly premium for drug coverage is $40 per month. Among the 72% of PDP enrollees who pay a monthly premium, their average monthly premium is $57.

Roughly one-third of PDP enrollees without LIS (35%, or 5.1 million) pay premiums above zero but less than $30 per month, but 1 in 5 (20%, or 2.9 million) pay at least $100 per month for their Part D plan (Figure 6). In contrast, less than 1% of non-LIS MA-PD enrollees pay $100 per month or more in Part D premiums.