Medicare IRMAA Tier Calculator (2025 Brackets)

How this calculator works

Medicare's Income-Related Monthly Adjustment Amount (IRMAA) raises the Part B and Part D premiums for higher-income beneficiaries. The IRMAA mechanism lives in two parallel statutes — 42 U.S.C. § 1395r(i) for Part B and 42 U.S.C. § 1395w-114a for Part D — and the bracket tables are republished each fall by the Social Security Administration. The 2025 tables came out under SSA-2024-31. This calculator maps the beneficiary's 2023 modified adjusted gross income (MAGI) onto the 2025 tier, returns the monthly Part B and Part D premiums, the annual IRMAA surcharge, and the MAGI delta to the next-lower tier so bracket-management levers can be evaluated.

The two-year lookback

IRMAA is determined from the beneficiary's MAGI on the tax return TWO years before the current premium year. The 2025 tier is set by the 2023 return. The lookback reflects an administrative reality: the SSA needs the most recent return that has been filed and processed by the IRS by the time premium notices go out in late autumn of the preceding year. Returns for 2024 are not filed until April 2025, are not fully processed until summer 2025, and premium notices for 2025 go out in November 2024 — so the 2023 return is the most recent one available when premiums are set.

The lookback is the single most surprising feature of IRMAA to newly-enrolled beneficiaries. A one-time income event in 2023 — a large Roth conversion, the sale of a business, the sale of an appreciated property, or even a large final-year working bonus — can set the 2025 premium two years later, even when 2024 and 2025 actual income are much lower. The premium is set on a snapshot of the past, not a forecast of the present.

What counts as MAGI for IRMAA

MAGI for IRMAA equals adjusted gross income (Form 1040 line 11) plus tax-exempt interest (Form 1040 line 2a — typically municipal-bond interest). That is the entire definition under 42 U.S.C. § 1395r(i)(4). It does NOT add back foreign earned income exclusion, foreign housing exclusion, or other items sometimes included in other MAGI definitions. The IRMAA MAGI is narrower than the ACA-marketplace MAGI and narrower than the Roth-contribution-eligibility MAGI.

The only meaningful surprise for most retirees is municipal-bond interest. Many high-income retirees hold a sizable muni allocation specifically to keep AGI low — and then discover that the muni interest is added back into MAGI for IRMAA, pushing them into a higher bracket than the bond-bracket math suggested. The fix is to model the muni interest line item explicitly when projecting MAGI for IRMAA, not just AGI.

2025 IRMAA brackets (SSA-2024-31)

For single filers (also head of household and qualifying widow(er)):

• MAGI at or below $103,000 — no IRMAA.
• $103,001 to $129,000 — Tier 1.
• $129,001 to $161,000 — Tier 2.
• $161,001 to $193,000 — Tier 3.
• $193,001 to $500,000 — Tier 4.
• Above $500,000 — Tier 5.

For married filing jointly:

• MAGI at or below $206,000 — no IRMAA.
• $206,001 to $258,000 — Tier 1.
• $258,001 to $322,000 — Tier 2.
• $322,001 to $386,000 — Tier 3.
• $386,001 to $750,000 — Tier 4.
• Above $750,000 — Tier 5.

For married filing separately (with spouse, during the tax year):

• MAGI at or below $103,000 — no IRMAA.
• $103,001 to $397,000 — Tier 4 (no Tier 1, 2, or 3).
• Above $397,000 — Tier 5.

The MFS schedule is a statutory quirk that skips Tiers 1, 2, and 3 entirely — the floor drops directly to Tier 4 above $103,000 of MAGI. Congress added this in 2003 to prevent income-splitting arbitrage by high-income married couples who file separately while continuing to share a household.

2025 Part B and Part D surcharges

The 2025 standard Part B premium is $174.70 per month. The Part B IRMAA add-ons by tier:

• Tier 0 — $0 (total Part B $174.70).
• Tier 1 — $69.90 (total Part B $244.60).
• Tier 2 — $174.70 (total Part B $349.40).
• Tier 3 — $279.50 (total Part B $454.20).
• Tier 4 — $384.30 (total Part B $559.00).
• Tier 5 — $419.30 (total Part B $594.00).

Part D plans set their own basic premiums — there is no national base — so the Part D IRMAA shows up as an add-on to whatever the beneficiary's chosen plan charges:

• Tier 0 — $0.
• Tier 1 — $13.70.
• Tier 2 — $35.30.
• Tier 3 — $57.00.
• Tier 4 — $78.60.
• Tier 5 — $85.80.

The Part D IRMAA goes to Medicare even though the underlying plan premium is paid to the private Part D plan sponsor.

The cliff: why $1 of extra income costs $1,500

IRMAA brackets are CLIFFS, not phase-ins. The marginal effective rate on the dollar that crosses a bracket edge can be extraordinarily high. A single filer with $129,000 of MAGI pays the Tier 1 surcharges — $69.90 Part B plus $13.70 Part D, or $83.60 per month, or $1,003.20 per year. The same filer with $129,001 of MAGI pays the Tier 2 surcharges — $174.70 plus $35.30, or $210.00 per month, or $2,520.00 per year. The extra dollar of MAGI triggers an extra $1,516.80 of annual surcharge — an effective marginal rate well over 100% on that dollar.

For married couples, both spouses pay the same tier individually, so the cliff cost doubles. A married couple with MAGI $1 over the MFJ Tier 1 floor pays roughly $2,006 per year more than a couple at $1 under. The brackets create powerful incentives to manage MAGI to land just below a cliff rather than just above it, particularly in years with discretionary income items (Roth conversions, capital-gain realizations, large IRA distributions).

Worked example 1: comfortably below Tier 1

A 70-year-old single retiree has 2023 MAGI of $80,000 — $75,000 of AGI plus $5,000 of tax-exempt interest. The beneficiary has chosen a Part D plan with a $40 basic premium.

• 2025 tier: Tier 0 (no IRMAA).
• Monthly Part B premium: $174.70 (base) plus $0 IRMAA = $174.70.
• Monthly Part D premium: $40.00 (plan) plus $0 IRMAA = $40.00.
• Annual IRMAA surcharge: $0.
• Headroom to next cliff (Tier 1): $23,001 of additional MAGI before the cliff fires.

The beneficiary is comfortably below the IRMAA threshold. The $23,001 of headroom is the budget for a Roth conversion in 2023 before the cliff fires; a small conversion would not push the beneficiary out of Tier 0.

Worked example 2: Tier 2, with a SSA-44 opportunity

A 67-year-old single retiree had 2023 MAGI of $150,000 — they were still working at a high-income consulting role through mid-2023 and retired in October. The 2025 IRMAA tier lands at Tier 2.

• 2025 tier: Tier 2.
• Monthly Part B premium: $174.70 plus $174.70 IRMAA = $349.40.
• Monthly Part D premium: $40.00 plus $35.30 IRMAA = $75.30.
• Annual IRMAA surcharge: 12 times ($174.70 plus $35.30) = $2,520.00.
• MAGI reduction to drop to Tier 1: $21,000 (down to $129,000 or lower would land in Tier 1).
• Annual savings if one tier lower: $1,516.80.

The beneficiary's 2024 income is much lower (retirement year, no consulting income) and 2025 is lower still. Work stoppage is a qualifying Life-Changing Event on Form SSA-44. The beneficiary can file SSA-44 with the SSA, supply estimated 2025 MAGI (say $50,000), attach evidence of the work stoppage (termination letter or final pay stub plus a statement that they have not returned to work), and the SSA will recompute 2025 IRMAA using the estimate. If the recomputation drops the beneficiary to Tier 0 for 2025, the $2,520 of surcharge is refunded for premium periods already paid at the higher rate and adjusted forward for the remainder of the year. The reconsideration is for 2025 only; 2026 will use the actual 2024 return (which is also low), so the SSA-44 is most valuable for the first year of retirement.

Worked example 3: Tier 5, no SSA-44 path

A 72-year-old retired surgeon and her spouse sold a long-held practice partnership in 2023, realizing a large capital gain. 2023 MAGI on the joint return came in at $1,200,000. The 2025 IRMAA tier lands at Tier 5 for both spouses (MFJ).

• 2025 tier: Tier 5.
• Monthly Part B premium per spouse: $174.70 plus $419.30 IRMAA = $594.00.
• Monthly Part D premium per spouse: $50.00 (Part D plan) plus $85.80 IRMAA = $135.80.
• Annual IRMAA surcharge per spouse: 12 times ($419.30 plus $85.80) = $6,061.20.
• Annual IRMAA surcharge for the couple: roughly $12,122.

The sale-of-a-practice gain is NOT a Life-Changing Event under Form SSA-44 — the SSA-44 list covers marriage, divorce, work stoppage, work reduction, pension loss, income property loss, and settlement payments, but it does not cover discretionary asset sales or one-time capital gains. The $12,122 of 2025 IRMAA is the price of the timing of the sale. For 2026, the standard two-year lookback applies to the 2024 return — if 2024 MAGI is back to a normal retirement-income level, 2026 IRMAA will reset to a lower tier (or to Tier 0).

The practitioner planning lesson is to model IRMAA before realizing a large gain. A $1.2M MAGI year that produces a large income-tax bill ALSO triggers a $12K IRMAA surcharge two years later. Moving the gain across tax-year boundaries, structuring an installment sale, or contributing to a charitable remainder trust to spread the recognition over multiple years can reduce the IRMAA hit.

The Life-Changing Events list (Form SSA-44)

Form SSA-44 ("Medicare Income-Related Monthly Adjustment Amount — Life-Changing Event") allows a beneficiary to request reconsideration when current income is materially lower than the two-year-lookback return because of a qualifying event. The eight qualifying events are:

1. Marriage.
2. Divorce or annulment.
3. Death of a spouse.
4. Work stoppage (retirement).
5. Work reduction (substantial cut in hours or income).
6. Loss of income-producing property (involuntary — e.g. natural disaster).
7. Loss or reduction of pension income.
8. Settlement payment from a former employer.

The beneficiary supplies a more-recent year-estimated AGI and tax-exempt interest, attaches evidence of the qualifying event, and the SSA recomputes IRMAA using the estimate. The reconsideration covers the CURRENT calendar year only; IRMAA reverts to the standard two-year lookback in the following year. SSA-44 is the single most powerful IRMAA-management lever for newly-retired Medicare beneficiaries whose pre-retirement income year is driving an inflated tier.

Events NOT on the list and therefore NOT eligible for SSA-44 reconsideration: large one-time capital gains (sale of a business, sale of an appreciated property), Roth conversions, IRA distributions, inheritance, gambling winnings, or any discretionary income realization. The form is for unwanted income SHOCKS, not for tax-planning choices the taxpayer made.

Bracket-management strategies

For the CURRENT tax year (not yet filed), the highest-leverage strategies for retirees are:

Time Roth conversions to land in low-IRMAA years. A Roth conversion adds dollar-for-dollar to MAGI under 26 U.S.C. § 408A. A large conversion in a year already near a cliff is expensive on both income tax and IRMAA — the conversion creates two years of inflated premiums under the lookback. The classic Roth-ladder window is the gap between full retirement and the start of Social Security or RMDs, when MAGI is naturally low.

Harvest capital losses to offset realized gains. Realized losses reduce AGI dollar-for-dollar (up to $3,000 per year of net loss against ordinary income, with the remainder carried forward, under 26 U.S.C. § 1211). The harvested loss can offset a gain that would otherwise push MAGI over a cliff.

Substitute Qualified Charitable Distributions for cash charitable giving. Under 26 U.S.C. § 408(d)(8), a Qualified Charitable Distribution (QCD) of up to $108,000 per year in 2025 (indexed annually) from a traditional IRA satisfies the RMD without adding to MAGI. A cash gift from a taxable account, by contrast, does not reduce MAGI — the QCD substitution is the same charitable outcome with a different tax treatment. For retirees who are already charitably inclined and subject to RMDs, the QCD is almost always the right vehicle.

Reconcile municipal-bond interest into the MAGI calculation. Muni interest is tax-exempt for income-tax purposes but is added back for IRMAA MAGI. A retiree with $100,000 of AGI and $20,000 of muni interest has $120,000 of IRMAA MAGI — not $100,000. Many retirees do not realize this and are surprised when the IRMAA tier comes in higher than the AGI suggested.

Defer additional discretionary income. If MAGI for the current year is already near a cliff, deferring an additional IRA distribution, Roth conversion, or capital-gain realization into the next tax year can land both years in lower tiers than a single concentrated year.

For a CLOSED tax year (return already filed), the only retroactive lever is Form SSA-44, and only if a Life-Changing Event applies.

Part D quirks

Part D IRMAA has two structural differences from Part B IRMAA worth knowing about:

The Part D base premium is plan-specific. Each Part D plan sets its own basic premium. The 2025 national average for stand-alone Part D plans is roughly $35 to $40 per month, but plan-specific premiums range from $0 (some Medicare Advantage plans bundling Part D) to $80 or more for richer stand-alone PDP plans. The Part D IRMAA add-on is the same across all plans for a given tier; the variation is in the plan basic premium.

Part D IRMAA is paid to Medicare, not to the plan. The beneficiary's Part D plan premium goes to the plan sponsor (the private insurance company offering the Part D coverage). The Part D IRMAA add-on is paid separately to Medicare — typically deducted from Social Security benefits along with the Part B premium. If the beneficiary is not yet receiving Social Security, the SSA bills the IRMAA directly.

Late enrollment penalty. Separate from IRMAA, beneficiaries who delay Part D enrollment past their initial enrollment window without continuous creditable drug coverage owe a late enrollment penalty equal to roughly 1% of the national base Part D premium per month of delay, permanently added to the Part D premium. This calculator does NOT model the late enrollment penalty — it is a separate mechanism from IRMAA.

Common errors

The most common errors in IRMAA projection work, in rough order of frequency:

Forgetting the two-year lookback. Beneficiaries plan around the wrong tax year. The 2025 tier is set by 2023 MAGI, not 2024 or 2025 MAGI. Practitioners modeling a multi-year retirement plan should be explicit about which year sets which year's IRMAA.

Excluding municipal-bond interest from MAGI. Muni interest is added back for IRMAA MAGI. Many retirees treat AGI as a proxy for IRMAA MAGI and miss the muni line.

Ignoring the cliff. Treating IRMAA as a phase-in (where each dollar of MAGI adds a small surcharge) rather than a cliff (where the dollar that crosses the edge triggers the full tier-jump). The cliff math is the entire point of bracket-management strategy.

Assuming a one-time income event will trigger SSA-44 reconsideration. SSA-44 covers the eight Life-Changing Events listed on the form. Discretionary income realizations — Roth conversions, asset sales, large IRA distributions — are not on the list and are not eligible for reconsideration.

Filing SSA-44 too early or too late. The form is forward-looking — it asks the beneficiary to estimate income for the year the event occurred or the year after. Filing for a prior year that has already closed is procedurally awkward; the cleaner path is to wait for the standard two-year-lookback adjustment to catch up in the following year.

Confusing IRMAA MAGI with other MAGI definitions. The IRMAA MAGI (AGI plus tax-exempt interest) is the narrowest MAGI in the federal code. The ACA-marketplace MAGI, the Roth-contribution-eligibility MAGI, and the Social-Security-taxability MAGI all have broader add-back rules.

What this calculator does not do

This is a planning and screening tool. It does NOT file Form SSA-44 — that goes through the SSA. It does NOT determine Medicare enrollment or process premium payments. It does NOT compute the Part D late enrollment penalty, the Part A premium for non-quarter-credit beneficiaries, or any Medicare Advantage premium differences. It does NOT include Medigap premium projections. It uses the 2025 brackets (SSA-2024-31) only; for 2026 and later, the SSA will publish updated tables in October or November of the preceding year and this calculator will be refreshed. The MAGI definition used here is the IRMAA-narrow definition — confirm with the beneficiary's CPA whether the relevant return MAGI matches that definition.

How this page is maintained

The IRMAA framework has been stable since MIPPA 2008 added the Part D piece. The bracket thresholds are indexed annually for inflation under 42 U.S.C. § 1395r(i)(6) (Tier 1 through Tier 4) — the SSA publishes the upcoming-year brackets in late October or early November of the preceding year. The Tier 5 floor ($500K single / $750K MFJ) is statutorily fixed for 2020 through 2027 and only begins annual indexing in 2028 under the Bipartisan Budget Act of 2018. The surcharge amounts are reset each year based on the Part B and Part D actuarial costs. This calculator is updated each November when the SSA publishes the new tables.

Last reviewed: 2026-05-16 against 42 U.S.C. § 1395r(i) (Part B IRMAA), 42 U.S.C. § 1395r(i)(4) (MAGI definition and two-year lookback), 42 U.S.C. § 1395w-114a (Part D IRMAA), 42 C.F.R. § 408.20 (Part B premium calculation), SSA-2024-31 (2025 IRMAA bracket tables), Form SSA-44 (Life-Changing Event reconsideration), the Medicare Improvements for Patients and Providers Act of 2008 (MIPPA, Pub. L. 110-275, originating Part D IRMAA), the Medicare Modernization Act of 2003 (MMA, Pub. L. 108-173, originating Part B IRMAA), 26 U.S.C. § 408A (Roth conversions), and 26 U.S.C. § 408(d)(8) (Qualified Charitable Distributions).