Medicare IRMAA Surcharge History

Josh · Last updated: May 8, 2026

Last verified: May 9, 2026 against CMS 2026 IRMAA tables + Medicare Trustees Reports

From the desk of Josh: financial modeling at a top private equity firm. See more by Josh.

IRMAA top-tier Medicare Part B monthly surcharge from $161/month in 2007 to $657/month in 2026, with major Medicare legislation annotated.

Sources: CMS annual Medicare Part B premium notices, Federal Register, SSA Form SSA-44 documentation, Medicare Modernization Act of 2003 legislative history.

IRMAA top-tier Part B monthly surcharge, 2007-2026

Tap or hover an event marker at the top of the chart to read the legislation summary. Data points show the top marginal rate for each year shown.

$161

2007 origin

Top-tier monthly surcharge at IRMAA introduction. Standard Part B premium that year was $93.50.

2 yrs

MAGI lookback

2026 IRMAA based on 2024 MAGI. One-time income events have a 2-year delayed impact.

$657

2026 top tier

Per month per person. Plus ~$90 Part D IRMAA. Married couples both at top tier pay roughly $1,500/mo combined.

The major changes

IRMAA has been shaped by three major changes since its 2007 introduction: ACA Part D extension, BBA 2018 top-tier creation, and the 2020 start of inflation indexation.

2003 / 2007

Medicare Modernization Act creates IRMAA

The Medicare Modernization Act of 2003 (the same Act that created HSAs) added income-related premium adjustments to Medicare Part B starting in 2007. The original 2007 structure had four tiers: standard premium for individuals with modified AGI under $80,000 single / $160,000 MFJ, plus three surcharge tiers above that. The top-tier monthly surcharge was $161.40/month in 2007 (in addition to the standard $93.50 base premium). The IRMAA structure is the closest the U.S. has come to means-tested Medicare; 95% of beneficiaries pay only the base premium.

2010 / 2011

Affordable Care Act extends IRMAA to Part D

The ACA of 2010 extended the income-related surcharge to Medicare Part D (prescription drug coverage), effective 2011. The Part D IRMAA uses the same MAGI thresholds as Part B but a different (smaller) surcharge formula. A high-income beneficiary in 2026 pays the Part B IRMAA surcharge plus a Part D IRMAA surcharge (typically $80-$90/month additional at the top tier).

2018

Bipartisan Budget Act adds new top tier

Before 2018, the top IRMAA tier kicked in at MAGI above $214,000 single / $428,000 MFJ. The Bipartisan Budget Act of 2018 added a new top tier above MAGI $500,000 single / $750,000 MFJ, effective 2019. This created a fifth IRMAA bracket and pushed the highest surcharge from $428.60/month in 2018 to $460.50/month in 2019. The 2018 change explicitly targeted high-net-worth retirees, particularly those receiving large IRA RMDs or Roth conversion income.

2007-2019

MAGI thresholds frozen for 12 years

The original 2007 IRMAA MAGI thresholds ($80K single / $160K MFJ for the first surcharge tier) were not inflation-indexed. From 2007 through 2019, the thresholds stayed flat in nominal dollars while wages and inflation grew, which silently pulled more retirees into IRMAA territory each year. Roughly 5% of Medicare beneficiaries paid IRMAA in 2007; by 2019 that share was approximately 8%. Indexation began in 2020.

2020

Inflation indexation begins

Starting in 2020, IRMAA MAGI thresholds were indexed to chained CPI (the same indexation method used for tax brackets after TCJA). This slowed the rate at which retirees were pulled into IRMAA but did not reverse the 12 years of bracket creep that preceded indexation. The 2026 first-tier threshold is approximately $109,000 single / $218,000 MFJ (vs. the original $80K / $160K from 2007).

2023

Standard premium decreases and IRMAA follows

The standard Medicare Part B premium decreased from $170.10 in 2022 to $164.90 in 2023 (the first decrease in over a decade), driven by the unwind of higher 2022 premiums that had funded a one-time Aduhelm dementia drug coverage decision. IRMAA surcharges follow the standard premium proportionally, so the top-tier surcharge dropped from $578.30/month in 2022 to $560.50/month in 2023.

2026

Where IRMAA stands today

The 2026 standard Part B premium is approximately $185/month. The top-tier IRMAA surcharge (MAGI above approximately $500K single / $750K MFJ) is $657.20/month, bringing total Part B to roughly $842/month for the highest-income retirees. Part D IRMAA at the top tier adds another $90 or so. Married couples both at the top tier pay this twice. The 2-year MAGI lookback means 2026 IRMAA is based on 2024 income, which can produce surprises for retirees whose income spiked once (Roth conversion, business sale, real estate sale) two years prior.

Things you might not know

IRMAA is a cliff, not a slope. Unlike tax brackets where only income above a threshold gets the higher rate, IRMAA applies the higher tier surcharge to your entire Medicare premium. One dollar over a bracket can cost you several thousand dollars annually. This makes year-end income management much more impactful for retirees near a bracket boundary.
The MAGI thresholds were frozen for 12 years. The original 2007 thresholds ($80K single / $160K MFJ) stayed static through 2019, silently pulling more retirees into IRMAA each year. Indexation began in 2020 but the bracket creep from 2007-2019 was never reversed.
Roth conversions can trigger IRMAA two years later. A large Roth conversion in 2024 increases your 2024 MAGI, which determines your 2026 IRMAA. Many financial planners specifically time conversions to avoid the 2-year-back IRMAA effect, particularly around age 63 (the last year before the Medicare-enrollment lookback).
Married couples can pay two surcharges. If both spouses are on Medicare and the couple's MFJ MAGI lands in a top tier, both spouses pay the surcharge separately. So at the top tier in 2026 a couple pays roughly $1,314/month (2 × $657) just in Part B surcharge, plus another $180/month in Part D surcharge.
SSA Form SSA-44 can reduce IRMAA after a life-changing event. If you've experienced retirement, work stoppage, divorce, marriage, death of a spouse, or other defined "life-changing events" that reduced your income, you can request an IRMAA re-determination via Form SSA-44 with documentation. Approval typically follows within 1-3 months and can save thousands annually for retirees who triggered a high tier from a one-time income event.

Frequently Asked Questions

What is IRMAA?

IRMAA (Income-Related Monthly Adjustment Amount) is the additional monthly premium surcharge that high-income Medicare beneficiaries pay on top of the standard Medicare Part B and Part D premiums. It was introduced for Part B in 2007 (Medicare Modernization Act of 2003) and extended to Part D in 2011 (Affordable Care Act). The surcharge is determined by your modified adjusted gross income from two years prior - so 2026 IRMAA is based on 2024 MAGI.

What are the 2026 IRMAA brackets?

The 2026 IRMAA brackets (MAGI from 2024) are approximately: under $109K single / $218K MFJ pays the standard premium with no surcharge. Tier 1: $109K-$137K single / $218K-$274K MFJ. Tier 2: $137K-$172K / $274K-$344K. Tier 3: $172K-$208K / $344K-$416K. Tier 4: $208K-$500K / $416K-$750K. Top tier: above $500K single / $750K MFJ. Each tier adds progressively more to the standard $185/month Part B premium plus separate Part D additions.

How does the 2-year MAGI lookback affect IRMAA?

Medicare uses your modified AGI from two years prior to determine your current-year IRMAA. So 2026 IRMAA is based on your 2024 tax return. This creates timing issues for retirees: a one-time income spike (Roth conversion, business sale, large capital gain) in 2024 will increase your 2026 IRMAA, even if 2026 income is lower. You can request a re-determination via SSA Form SSA-44 if you've had a 'life-changing event' (retirement, divorce, work stoppage, marriage, death of spouse) that reduced your MAGI.

Is IRMAA a tax cliff or progressive?

IRMAA is structured as a 'cliff' - one dollar over a bracket threshold can move you to the next tier and increase your annual surcharge by hundreds or thousands of dollars. Unlike tax brackets where only income above the threshold gets the higher rate, IRMAA applies the higher tier surcharge to your entire Medicare premium. This makes year-end income management (Roth conversion timing, capital gains harvesting, deductible IRA contributions) much more impactful for retirees near a bracket boundary than for those well inside a bracket.

How can I avoid IRMAA?

Several strategies for retirees: (1) Roth conversions in lower-income years before age 63 (the lookback for age-65 enrollment is age-63 income); (2) Qualified Charitable Distributions from IRAs at age 70.5+, which reduce MAGI; (3) tax-loss harvesting to offset capital gains; (4) HSA contributions while still working in HDHP coverage; (5) timing capital gain realization to keep MAGI just under a bracket threshold; (6) avoiding large one-time income events two years before Medicare enrollment. The 2-year lookback is the most consequential constraint.

Are there proposals to expand IRMAA?

Yes. Various Medicare reform proposals have suggested lowering the IRMAA thresholds (pulling more middle-income retirees into surcharge territory), eliminating the indexation that began in 2020, or stacking additional surcharge tiers above the current top. The 2018 BBA was the most recent expansion. Conservative retirement modeling assumes IRMAA thresholds may be cut back to nominal 2007 levels in real terms over the next decade as Medicare faces funding pressure.

To stress-test whether a Roth conversion or RMD pushes you across an IRMAA cliff, use our retirement calculator alongside the tax bracket calculator. For the wage-base side of Medicare and Social Security, see Social Security wage base history. For sources and update cadence, see our methodology.

Social Security Wage Base History

Coming Soon

SSA contribution and benefit base from 1937 to 2026.