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Medicare Surcharge Calculator
IRMAA Cliff Calculator 2026
Find your Medicare Part B and Part D surcharge tier, see how far you are from the next income cliff, and calculate your Roth conversion headroom. Based on 2026 CMS.gov brackets with 2024 MAGI lookback.
This tool is independent education for federal employees and retirees. It is not tax, legal, or investment advice, and FedTools is not your fiduciary. Verify your situation with a fee-only financial planner, tax advisor, or SSA directly. See our editorial standards and terms for details.
2026 estimate — verify with SSA or a tax advisor
Uses 2026 IRMAA brackets (CMS.gov / SSA.gov). The 2-year lookback means your 2024 MAGI determines your 2026 surcharges. MAGI = AGI + tax-exempt interest. Roth withdrawals and HSA distributions generally do not count as MAGI. This is educational — not tax advice. Verify with SSA if your income has recently changed significantly.
Filing Status
2024 MAGI Components
Enter your estimated 2024 income components (for 2026 IRMAA) — or your projected 2026 income to model 2028 surcharges. Leave blank for any component that does not apply.
W-2 wages, self-employment income, or military pay.
FERS annuity, CSRS pension, or other retirement annuity.
Taxable distributions from traditional (pre-tax) TSP accounts count as MAGI.
Roth conversions increase MAGI dollar-for-dollar — use the headroom meter below to size conversions.
Long-term and short-term realized gains from asset sales.
Shown on Form 1040 line 2a. Tax-exempt but still counts toward IRMAA MAGI.
2026 IRMAA brackets at a glance
Per-person annual surcharges for single filers (2024 MAGI → 2026 premiums). Joint thresholds are exactly double; MFS filers jump from $0 to Tier 4 above $109,000. Source: CMS.gov / SSA.gov.
2026 Medicare IRMAA annual surcharges by single-filer MAGI bracket (CMS.gov)
2024 MAGI (single)
Part B surcharge/yr
Part D surcharge/yr
Combined/yr
≤ $109,000
$0
$0
$0/year
$109,001 – $137,000
$974
$174
$1,148/year
$137,001 – $171,000
$2,435
$450
$2,885/year
$171,001 – $205,000
$3,895
$725
$4,620/year
$205,001 – $500,000
$5,356
$998
$6,354/year
Above $500,000
$5,843
$1,098
$6,941/year
Per-person amounts. Joint couples pay twice the per-person surcharge. MFS filers skip Tiers 1–3 above $109,000. Amounts are annual surcharges only — add the $202.90/month standard premium ($2,434.80/year) for total Part B cost. Last reviewed August 2026.
How IRMAA works — and why it catches federal retirees off guard
IRMAA is a Medicare surcharge that applies when your Modified Adjusted Gross Income (MAGI) crosses one of five income thresholds. SSA determines your surcharge using your tax return from two years prior — the 2-year lookback. Your 2024 income determines your 2026 IRMAA, and your 2026 income will determine your 2028 surcharges.
Federal retirees face a compounding MAGI problem. A FERS annuity, traditional TSP withdrawals, and a Roth conversion all land in the same MAGI bucket. Retirees who planned around their W-2 income are sometimes surprised to find that a planned Roth conversion or a TSP Required Minimum Distribution pushed them into the next IRMAA tier — adding over $1,000 per person per year in Medicare costs.
Roth IRA qualified withdrawals do not count as MAGI — a key advantage for retirees who built Roth balances before retirement. HSA distributions used for qualified medical expenses also do not increase MAGI. Traditional TSP withdrawals, by contrast, count dollar-for-dollar as ordinary income and therefore as MAGI.
The IRMAA cliff: why $1 can cost $1,000+
Unlike a graduated income tax, IRMAA is a step function. When your MAGI crosses a threshold, your entire Medicare surcharge jumps to the new tier rate — not just the income above the line. A single dollar of additional income at the Tier 1 / Tier 2 boundary adds $1,737/year per person in extra Medicare costs (the difference between the $1,148 Tier 1 surcharge and the $2,885 Tier 2 surcharge).
Worked example: the Roth conversion cliff
Single retiree · FERS annuity $72,000 · TSP RMD $32,000 · MAGI = $104,000 (no IRMAA)
Scenario A — No Roth conversion: MAGI $104,000 → No IRMAA. Medicare costs = standard only.
Scenario B — $10,000 Roth conversion: MAGI $114,000 → crosses $109,000 → Tier 1. Extra cost: $1,148/year.
Scenario C — $5,000 conversion (headroom-limited): MAGI $109,000 exactly → still no IRMAA. Conversion tax + no IRMAA penalty.
This calculator shows the exact headroom for Scenario C.
The married-filing-separately IRMAA trap
Married couples who file separately and lived together at any point during the year face one of the harshest bracket structures in the Medicare system. Above $109,000, MFS filers skip Tiers 1 through 3 entirely and land at the Tier 4 surcharge rate — the same rate applied to single filers with incomes above $205,000. A federal retiree with $130,000 of MAGI who files jointly would owe no IRMAA (below the $218,000 joint threshold). The same retiree filing MFS would owe $6,354/year in surcharges.
The MFS election is occasionally considered when couples have very different tax situations. Anyone weighing MFS should model the full IRMAA impact as part of that analysis — this calculator's MFS mode shows the tier jump explicitly.
Appealing IRMAA after a life-changing event
If your income has dropped significantly from the year SSA is using, you can request that SSA use a more recent year. Qualifying life-changing events include:
Retirement or reduction in work hours (the most common trigger for federal retirees)
Death of a spouse
Divorce or annulment
Loss of pension income
Loss of income-producing property through disaster or foreclosure
File Form SSA-44 with your local SSA office or call SSA at 1-800-772-1213. Include documentation of the event (e.g., separation from service SF-50, pension award letter). SSA will estimate your current-year income and, if it places you in a lower tier, adjust your premiums going forward.
Frequently asked questions
IRMAA — Income-Related Monthly Adjustment Amount — is a Medicare surcharge added on top of the standard Part B and Part D premiums when your income exceeds certain thresholds. SSA determines your IRMAA each year based on your MAGI from two years prior (the "2-year lookback"). For 2026, SSA uses your 2024 MAGI. The standard Part B premium is $202.90/month; IRMAA adds up to $486.58/month more per person at the highest tier.
For IRMAA, MAGI equals your Adjusted Gross Income (line 11 of Form 1040) plus tax-exempt interest income (line 2a). Traditional TSP or 401(k) withdrawals, Roth conversions, capital gains, wages, and pension income all count. Roth IRA withdrawals (from qualified distributions) and HSA distributions generally do not count as MAGI.
Each IRMAA tier has a hard income threshold. Crossing it by even $1 moves you into the next tier and can add $1,000–$1,500+ per person per year in surcharges. For federal retirees planning Roth conversions, the "conversion headroom" shown in this calculator tells you exactly how much you can convert while staying in your current tier. A single dollar over the cliff triggers the full next-tier surcharge — this is the IRMAA cliff problem.
Married Filing Separately (MFS) filers who lived with their spouse at any point during the year face a compressed bracket structure. Above $109,000, MFS filers skip Tiers 1–3 entirely and land at the Tier 4 surcharge rate — the same rate that applies to single filers earning over $205,000. This MFS penalty is one of the steepest in the Medicare surcharge structure.
Yes. If your income dropped due to a life-changing event — including retirement, reduction in work hours, divorce, death of a spouse, or loss of income-producing property — you can request that SSA use more recent income by filing Form SSA-44 (Medicare Income-Related Monthly Adjustment Amount — Life-Changing Event). SSA will then base your IRMAA on estimated current-year income rather than the 2-year lookback figure.