Which tax year does Medicare use to calculate IRMAA?

Quick Answer

Medicare uses your income from two years prior to calculate IRMAA. For example, your 2025 Medicare premiums are based on your 2023 tax return.

Detailed Explanation

IRMAA stands for Income-Related Monthly Adjustment Amount. It's an extra charge added to your Medicare Part B and Part D premiums if your income exceeds certain thresholds. The Social Security Administration handles this calculation, and they use the most recent federal tax return they have on file, which is typically two years old.So if you're enrolling in Medicare in 2025, SSA is looking at your 2023 adjusted gross income. If that income was above the threshold (which changes annually), you'll pay a higher premium. The surcharge is tiered, meaning the more you earned, the higher the added cost.This creates a real-world problem for people who recently retired or had a one-time income spike. Maybe you sold a rental property, took a large 401(k) distribution, or sold a business in 2023. Even if your 2024 and 2025 income are much lower, SSA still sees that 2023 number and applies the surcharge.The good news is you can appeal an IRMAA determination if your income has dropped significantly due to a qualifying life event, like retirement, divorce, or the death of a spouse. This is called a Life Changing Event appeal, and you file it using SSA Form SSA-44. It's worth doing if your current income genuinely doesn't reflect what SSA is using.

How This Applies in Utah

What This Means For You

For you, this means a high-income year two years ago can raise your Medicare premiums today, but if your income has dropped since then due to retirement or another major life change, you have options to appeal and potentially lower what you pay.

Disclaimer

‍How Resting Sycamore Advisors Uses CMS Data

Our Commitment to Reliable Medicare Information

At Resting Sycamore Advisors, we work to provide accurate, current, and trustworthy information about Medicare Advantage, Medicare Part D, and Special Needs Plans.

To do that, we use data published by the Centers for Medicare & Medicaid Services (CMS), which is the official source for Medicare plan and enrollment information.

CMS Data Sources We Rely On

Our Medicare plan pages and comparison tools are powered by CMS datasets, including:

  • Medicare Advantage and Part D Landscape Files for annual plan availability and benefit details
  • Plan Benefits Package (PBP) Files for detailed benefit and coverage information
  • Part C and Part D Performance Data for quality ratings and plan performance measures
  • Monthly Enrollment Data for enrollment counts by contract, plan, state, and county

When possible, we link to the original CMS resources so you can review the source material directly.

How Often We Update Our Data

We follow the CMS release schedule and update our website as new data becomes available.

Annual Plan Year Updates (September)

We load new plan year Landscape and PBP files before the Medicare Annual Enrollment Period (October 15 through December 7). We also monitor CMS.gov for updates or revisions and refresh our content when needed.

Mid-Year Updates

We update enrollment and performance data as CMS publishes revised files, which are typically released monthly or quarterly.

Ongoing Maintenance

We routinely monitor CMS announcements for corrections, reissued files, or other changes and update our pages accordingly.

Each plan page includes a Last Accessed date so visitors can see when the source information was most recently reviewed.

How We Prepare CMS Data for Our Website

CMS data can be difficult to read in raw form. To make it easier to use, we format and organize the data for clarity.

This includes:

  • Standardizing plan identifiers such as contract ID, plan ID, and segment
  • Normalizing terminology so common Medicare terms are presented consistently
  • Organizing plan information by state, county, and ZIP code to match how people shop for coverage

All data values come from CMS. We do not change the underlying values beyond formatting, organization, and presentation.

Version Tracking and Transparency

We keep internal records of the CMS dataset versions used on our site.

Major Version History

  • Current Version: CY2025 Medicare Advantage and Part D Landscape Files (v1.0, published October 2025)
  • Prior Version: None. Resting Sycamore Advisors first began publishing structured Medicare plan information in March 2025

If CMS issues corrected or revised files, we update our website to reflect the latest available version.

Important Limitations

Please keep the following in mind:

  • CMS is the official source of truth. For enrollment and coverage decisions, always confirm details with Medicare.gov or 1-800-MEDICARE.
  • Data timing can vary. Enrollment and performance updates may appear on our website a few weeks after CMS publishes changes.
  • Plan details can change. Plan availability, costs, and benefits may change. Always verify current details directly with the plan provider.

Need Help From Official Medicare Resources?

For personalized Medicare assistance, please use these official resources:

  • Medicare.gov Help Center — https://www.medicare.gov
  • 1-800-MEDICARE (1-800-633-4227) TTY: 1-877-486-2048
  • State Health Insurance Assistance Program (SHIP) — free local counseling for Medicare beneficiariesIf you want, I can also give you a shorter legal-style version for a footer or /disclaimer page summary.