Transparent method
The formula
Worked example
Example inputs
How to interpret the result
IRMAA thresholds work as a cliff, not a gradual slope, so crossing one by even a single dollar of income triggers the full surcharge tier for that entire income bracket, not a proportionally small increase matched to how far over the line the income actually landed.
Before you rely on it
What to check
Check current income against the specific official threshold amounts for the applicable lookback year, since MAGI from a prior year, not current income, is what typically determines the surcharge.
The common error
Where people go wrong with medicare IRMAA cliff calculator
Assuming a small amount of income over an IRMAA threshold produces a proportionally small surcharge increase. The cliff structure means crossing the line by even a modest amount can trigger the full next-tier surcharge.
Sensitivity evidence
How projected modified adjusted gross income changes the distance below threshold
| Projected modified adjusted gross income | Distance below threshold | Annual surcharge if crossed |
|---|---|---|
| $156,000 | $56,000 | $4,320 |
| $175,500 | $36,500 | $4,320 |
| $195,000worked example | $17,000 | $4,320 |
| $214,500 | -$2,500 | $4,320 |
| $234,000 | -$22,000 | $4,320 |
Every input, tested
Which input moves the distance below threshold most
| Input | Tested from | To | Distance below threshold at each end | Swing |
|---|---|---|---|---|
| Selected IRMAA threshold | $190,800 | $233,200 | -$4,200 to $38,200 | $42,400 (249%) |
| Projected modified adjusted gross income | $175,500 | $214,500 | $36,500 to -$2,500 | $39,000 (229%) |
| Combined monthly surcharge if crossed | $162 | $198 | $17,000 to $17,000 | none |
| Covered people | 1 | 3 | $17,000 to $17,000 | none |
Two variables at once
Distance below threshold by projected modified adjusted gross income and selected IRMAA threshold
| Projected modified adjusted gross income \ Selected IRMAA threshold | $169,600 | $212,000 | $254,400 |
|---|---|---|---|
| $156,000 | $13,600 | $56,000 | $98,400 |
| $175,500 | -$5,900 | $36,500 | $78,900 |
| $195,000 | -$25,400 | $17,000 | $59,400 |
| $214,500 | -$44,900 | -$2,500 | $39,900 |
| $234,000 | -$64,400 | -$22,000 | $20,400 |
Step by step
The worked example, input by input
| Input | Value used |
|---|---|
| Projected modified adjusted gross income | $195,000 |
| Selected IRMAA threshold | $212,000 |
| Combined monthly surcharge if crossed | $180 |
| Covered people | 2 |
| Distance below threshold | $17,000 |
| Annual surcharge if crossed | $4,320 |
Where the inputs come from
Projected modified adjusted gross income is your AGI plus tax-exempt interest, projected for the year that Medicare will use, which is the tax return from two years earlier. The threshold is the MAGI level for the next surcharge tier, which the Social Security Administration publishes for each year and filing status. The combined monthly surcharge is the additional Part B and Part D amount at that tier, and covered people is the number of people on Medicare in the household.
When the result stops applying
Thresholds and surcharges change every year, and the determination uses income from two years earlier, so a one-time spike such as selling a business can raise premiums later. You can appeal with Form SSA-44 after a life-changing event, such as retirement. There are several tiers, and this tool covers one at a time.
What to compare it with
Manage the drivers with the QCD tax savings and Roth conversion calculators, and the first-year RMD timing page, since RMDs count toward MAGI. The retirement healthcare cost calculator shows the wider medical budget, and the taxable Social Security page shows another effect of higher income.
People also ask
Frequently asked questions
What is the IRMAA Medicare surcharge?
The Income-Related Monthly Adjustment Amount is an extra charge added to Medicare Part B and Part D premiums for higher-income beneficiaries, based on income from two years earlier.
Which income does Medicare use?
Modified adjusted gross income from your tax return two years before, so the premiums you pay this year reflect income from the year before last.
Can I appeal an IRMAA charge?
Yes, if your income dropped because of a life-changing event such as retirement, marriage, divorce or the death of a spouse, by filing a request with the Social Security Administration.