Medicare’s IRMAA surcharge affects Part B and Part D premiums for those with higher incomes. It uses tax return data from two years prior to calculate additional fees. IRMAA applies to both Original Medicare and Medicare Advantage plans. We’ve listed the 2025 brackets below, along with 2024 and 2026 figures. https://www.federalpensionadvisors.com/post/2025-irmaa-brackets