Irmaa Brackets 2024 Part D. The irmaa is calculated on a sliding scale with five income brackets, topping out at $500,000 and $750,000 for individual and joint filing, respectively. The income limit for irmaa in 2024 is $103,000 for individuals and $206,000 for couples.

The social security administration (ssa) determines who pays an irmaa based on the income reported 2 years prior. Whether you have medicare part d coverage plays into your final bill.