Medicare Part D beneficiaries should brace for notable cost increases in 2026. The Centers for Medicare & Medicaid Services (CMS) has announced that the national average monthly bid amount for Part D plans will rise to $239.27 for 2026, up from $179.45 the previous year. The base beneficiary premium will also increase to $38.99, compared to $36.78 in 2025. These changes reflect the continued scaling back of the premium stabilization program, which was introduced to help beneficiaries manage transitions under new rules from the Inflation Reduction Act (IRA).
The premium stabilization program, which capped annual premium increases at $35 and provided a $15 monthly discount in 2025, will be less generous in 2026. The discount drops to $10 and the cap on year-over-year premium increases rises to $50. These adjustments may result in some standalone drug plan premiums rising more steeply than before. Furthermore, the tighter financial protections—risk corridors instituted last year—will revert to the pre-2025 standard corridors, potentially exposing plans (and thus consumers) to greater premium variability.
Significantly, out-of-pocket costs are also on the rise. The annual out-of-pocket cost cap for Part D will increase to $2,100 in 2026, up from $2,000 in 2025, reflecting indexing for inflation tied to the IRA’s overhaul of prescription drug spending. The deductible for standard plans is expected to increase slightly as well (the 2025 deductible was $590; the 2026 amount, while not finalized, is anticipated to be higher).
High-income enrollees will see Part D IRMAA (income-related premium surcharges) increase by more than 6% on average, according to projections, further raising costs for those subject to higher-income brackets.
Beneficiaries are encouraged to review plan details annually during the open enrollment period which runs from October 15th until December 7th, 2025, as these changes could mean significant differences in both premiums and out-of-pocket expenses in 2026.
More information about Medicare Part D can be found on the CMS website.