Calculate maximum IRA balance to avoid IRMAA surcharges at all 5 tiers
Note:
Calculations show the maximum IRA balance that would keep MAGI at or below each IRMAA tier threshold. In practice, you'd want to stay away from the limit by a few thousand dollars to avoid the IRMAA Tax Cliff.
Assumptions:
No tax-exempt interest or other MAGI adjustments
RMD is the only withdrawal from the IRA
Taxable Social Security calculated based on provisional income rules
IRMAA Surcharges: Part B + Part D combined.
IRMAA Thresholds as of 2025 brackets: Tier 1: MFJ $212,000 | Single $106,000 → Surcharge: $1,042.80/year (per person) Tier 2: MFJ $266,000 | Single $133,000 → Surcharge: $2,619.60/year (per person) Tier 3: MFJ $320,000 | Single $160,000 → Surcharge: $4,196.40/year (per person) Tier 4: MFJ $374,000 | Single $187,000 → Surcharge: $5,773.20/year (per person) Tier 5: MFJ $750,000 | Single $500,000 → Surcharge: $6,349.20/year (per person)
IMPORTANT NOTE These are values as of 2025. However the consumer price index increases at a rate of about 2.8% per year annually for the last 20 years, while the IRMAA tax increases at a rate of about 5.6% per year (it's tied to Medicare costs). This means that in the future the brackets will be adjusted, however the TAX will also be adjusted by about twice as much. Example: Tier 1 at 106k and 1K annual additional tax will become 109K with an 11K tax.