Irmaa For 2025 Brackets. For 2025, you’ll find several distinct income brackets that determine your irmaa surcharge. For 2025, the income brackets for part b and part d are the same.
Irmaa brackets basically, if you earn above certain levels — there are five brackets —. The 2025 irmaa brackets are determined by the centers for medicare & medicaid services (cms) and are based on income levels.