How Your Parent's Income Affects Medicare Premiums (MAGI and IRMAA Explained)

Most families assume that Medicare Part B costs the same for everyone — a fixed monthly premium, full stop. That is true for most enrollees, but not all. If your parent had a higher income in recent years, they may owe significantly more.

The mechanism is called IRMAA — the Income-Related Monthly Adjustment Amount. It is a surcharge added to Part B and Part D premiums based on your parent's Modified Adjusted Gross Income (MAGI) from two years prior. Understanding how it works matters both for setting accurate budget expectations and for knowing when and how to appeal it.

What Is MAGI in the Context of Medicare?

MAGI stands for Modified Adjusted Gross Income. For Medicare purposes, it is calculated as your parent's Adjusted Gross Income (AGI) from their federal tax return plus any tax-exempt interest income they received.

This is not a special calculation your parent does separately — it is derived directly from their tax return. Social Security uses the most recent tax return they have on file with the IRS, which is typically two years prior to the current year. This two-year lookback is important because it creates a timing mismatch: premiums in 2026 are based on 2024 income.

That creates situations where IRMAA feels unfair. A parent who retired in 2024 with a strong final year of wages may be paying elevated premiums in 2026 even though their retirement income is now much lower. This is one of the most common frustrations adult children encounter when managing a parent's Medicare costs — and it is also one of the most fixable.

How IRMAA Works: The Surcharge Tiers

Medicare's standard Part B premium for 2026 is approximately $185/month. If your parent's MAGI from 2024 was above $106,000 (single filer) or $212,000 (married filing jointly), they pay more.

The surcharges are structured in tiers. Approximate 2026 amounts:

For single filers:

For married filing jointly, the thresholds are approximately double the single-filer thresholds.

Part D (prescription drug) premiums are also subject to IRMAA surcharges that scale similarly, adding $12 to $81/month on top of whatever the Part D plan itself charges.

Combined, a high-income parent could pay $500-$800/month more than the standard rates. For a couple, double that. These are real numbers that need to be in any retirement income planning conversation.

Why Social Security Sends the IRMAA Notice (Not Medicare)

This confuses many families. Social Security Administration — not CMS or Medicare — determines and collects IRMAA. SSA uses IRS income data, calculates the surcharge, and deducts the additional premium directly from Social Security benefit payments.

If your parent's Part B premium is being deducted from their Social Security check, the IRMAA surcharge is bundled in — they may not even see a separate line item unless they know to look for it on their Social Security benefit statement.

If your parent is not yet collecting Social Security, or if the surcharge exceeds their Social Security benefit, Medicare will bill them quarterly for the combined premium amount.

When IRMAA Feels Wrong: The Life-Changing Event Appeal

Because IRMAA looks at income from two years ago, it can generate surcharges that no longer reflect your parent's actual financial situation. Medicare allows you to appeal IRMAA and have premiums recalculated based on more recent income if your parent experienced a qualifying life-changing event.

Qualifying life-changing events include:

• Retirement or reduction in work hours (this is the most common reason adult children file IRMAA appeals)
• Death of a spouse
• Divorce or annulment
• Loss of income-producing property due to a disaster or other event
• Reduction or loss of pension income due to bankruptcy or termination of a pension plan
• Marriage (if it changes the filing status in a way that affects premium calculation)

A general market downturn that reduced investment income is not a qualifying life-changing event. Neither is voluntary withdrawal from retirement accounts, selling a house, or receiving an inheritance.

To appeal, your parent (or you as their authorized representative) files Form SSA-44 with the Social Security Administration. You will need documentation of the life-changing event and an estimate of the current year's income. SSA will recalculate the premium based on the more recent estimate.

This is worth doing. If your parent retired mid-2024 but their 2024 tax return still shows a high income due to pre-retirement wages, they should file an SSA-44 to get 2026 premiums recalculated based on their expected 2025 income instead. The savings can easily be $100-$400/month or more.

The Two-Year Lag and Planning Around It

The two-year lookback creates predictable planning windows that savvy families use intentionally.

The year of retirement: The highest risk year for IRMAA surprises. If your parent worked full-time through mid-2024, their 2024 MAGI could be high enough to trigger surcharges in 2026 even though they are now living on a much smaller retirement income.

Roth conversions: If your parent did a large Roth IRA conversion in 2024 — converting a traditional IRA to Roth — that conversion amount counts as income for IRMAA purposes, potentially pushing them into a higher surcharge tier two years later. This is not always discussed when families execute Roth conversions, and the Medicare cost impact can partially offset the tax benefit of the conversion.

Capital gains from selling a home or investments: A large one-time capital gain in a given year can spike MAGI and trigger IRMAA two years later, even if your parent's ordinary income is modest. If your parent sold a vacation home or liquidated a significant investment portfolio in 2024, their 2026 Medicare premiums may be elevated as a result.

The key point: IRMAA is not a fixed annual thing. It resets every year based on income from two years prior. A parent who had high income in 2024 but low income in 2025 will see their surcharges drop in 2027 without any action needed. The trajectory matters, and it is worth knowing where your parent's MAGI is headed.

How to Find Out If Your Parent Is Paying IRMAA

The simplest way to check: look at your parent's Medicare card and their Social Security benefit statement (or quarterly Medicare bill). If Part B is costing more than the standard premium amount, IRMAA is the reason.

Your parent can also log in to ssa.gov to view their current benefit statement and Medicare premium deductions.

If they received a determination letter from SSA about their Part B and Part D premiums, that letter will explicitly state the IRMAA tier they are in and the income data SSA used. If the income data is wrong — for example, if SSA used an incorrect tax year — that is also appealable.

IRMAA and Medicare Advantage

If your parent is on a Medicare Advantage plan rather than Original Medicare, IRMAA still applies to the Part B premium they pay (everyone on Medicare pays Part B, even Medicare Advantage enrollees). If their Advantage plan includes drug coverage (MA-PD), the Part D IRMAA surcharge also applies.

One nuance: some Medicare Advantage plans offer a "Part B premium reduction" or "give back" benefit, returning a portion of the Part B premium to the enrollee as a credit. This reduction applies to the standard Part B premium and does not offset IRMAA surcharges.

Low-Income Protections: The Other Side of the Income Equation

While high-income seniors pay more through IRMAA, low-income seniors may pay less — or nothing — through Medicare Savings Programs (MSPs) and the Extra Help program.

Medicare Savings Programs are state-run programs that help pay Part B premiums and sometimes deductibles and coinsurance. The most comprehensive, the Qualified Medicare Beneficiary (QMB) program, pays premiums, deductibles, and coinsurance for beneficiaries with income below approximately $1,325/month (single, 2026 estimate). Importantly, QMB enrollees cannot legally be billed by providers for Medicare-covered services — this is a powerful protection many families do not know exists.

Extra Help (Low Income Subsidy) specifically covers Part D costs, reducing drug copays to as little as $12.65 per prescription. Eligibility is income-based, with limits around $1,955/month for a single individual (2026 estimate).

If your parent's income dropped significantly after retirement, it is worth checking whether they qualify for either program.

Why Understanding Income Effects Matters for Enrollment Decisions

When helping a parent choose between Original Medicare and Medicare Advantage, the premium comparison needs to include IRMAA where applicable. A Medicare Advantage plan marketed as "$0 premium" is not actually zero-cost if your parent is paying $259 or more per month in Part B due to IRMAA.

The correct comparison is total premiums across all coverage components — Part B (with any IRMAA surcharge), the plan premium itself, and Part D (with any IRMAA). This total is what your parent actually pays before any services are used, and it can vary significantly by income tier.

Our Medicare Enrollment Guide covers the full cost picture for families navigating enrollment — including how IRMAA affects the Original Medicare versus Medicare Advantage decision, how to use the SSA-44 appeal process if your parent's income has dropped, and how to avoid common premium calculation errors that cause families to budget incorrectly for their parent's healthcare costs in retirement.