Medicare uses your gross income, not your net pay, to determine whether you owe extra premiums

When Medicare calculates your Income-Related Monthly Adjustment Amount (IRMAA) — the extra premium you may pay for Part B and Part D — it looks at your gross income. Gross income is what you earn before taxes, Social Security withholding, and other deductions come out. Your net pay, the amount that actually lands in your bank account, does not matter for this calculation.

This distinction matters because your gross income is almost always higher than your net pay. If you are trying to understand whether you will owe extra Medicare premiums, you need to know your gross figure, not the take-home number on your pay stub.

Key Takeaways

  • Medicare counts your gross income (before taxes and deductions) when determining IRMAA premiums, not your net take-home pay.
  • The income figure Medicare uses comes from your federal tax return from two years prior, not your current year earnings.
  • If your income drops significantly due to retirement, job loss, or other life changes, you can report that change to Medicare and potentially lower your premiums.
  • Your gross income includes wages, self-employment income, interest, dividends, and certain other sources, but not all income counts the same way.

Which income figure Medicare actually uses

Medicare does not look at your current paychecks. Instead, it uses your Modified Adjusted Gross Income (MAGI) from your federal tax return filed two years before the year the premium takes effect. If you are turning 65 in 2025, Medicare will use your 2023 tax return to set your 2025 premiums.

Your MAGI is close to your gross income but includes some adjustments. It typically includes wages, self-employment income, interest, dividends, rental income, and certain other sources. It does not include Social Security benefits (unless you file a joint return and your combined income exceeds certain thresholds), but it does include tax-exempt interest from municipal bonds.

Because Medicare uses a two-year lag, your premiums may not reflect your current financial situation. This is why Medicare allows you to report a life-changing event if your income has dropped significantly since that tax return was filed.

What counts as income for Medicare premium purposes

Not all money you receive counts toward your IRMAA calculation. Wages, self-employment income, interest, dividends, capital gains, rental income, and distributions from retirement accounts all count. Certain types of income — such as Supplemental Security Income (SSI), some veterans benefits, and nontaxable combat pay — do not count.

If you are married and file jointly, Medicare combines both spouses' incomes. If you file separately, your income is calculated individually, but filing separately often results in higher IRMAA premiums because the income thresholds are much lower for people who file that way.

The income thresholds that trigger extra premiums change each year. In 2024, for example, a single person with MAGI over $103,000 begins to owe extra Part B premiums. These thresholds are adjusted annually for inflation.

How gross pay affects your Medicare premiums

The higher your gross income, the higher your IRMAA premiums. Medicare uses income brackets, and your premium increases in steps as your income rises. A single person with $103,000 in MAGI pays a different amount than someone with $150,000, which is different again from someone with $500,000.

Because Medicare counts gross income and uses a two-year lag, someone who retires mid-year may still owe high premiums based on the full year's earnings from two years earlier. This is another reason why reporting a life-changing event matters: if you retired, lost a job, or experienced a significant income drop, you can ask Medicare to recalculate your premiums based on your current-year income instead.

Reporting income changes to Medicare

If your income has dropped by $20,000 or more since the tax return Medicare is using, or if you experienced a life-changing event such as retirement, divorce, or death of a spouse, you can contact Social Security to report the change. You will need to provide documentation — a recent pay stub showing lower income, a letter from your employer, a divorce decree, or a death certificate, depending on the event.

Social Security will review your request and may recalculate your IRMAA based on your current-year income estimate. This can lower your premiums when ready, rather than waiting for the next year's adjustment based on your updated tax return.

You have until December 31 of the year following the year the change occurred to report it. If you miss that important date, you will have to wait until your next tax return is filed to see the adjustment reflected in your premiums.

Why Medicare does not use net pay

Medicare uses gross income because it is the standard measure of earnings on federal tax returns. Net pay varies widely depending on how many dependents you claim, what retirement contributions you make, and what other deductions you take. Gross income is consistent and verifiable through tax documents.

Using net pay would also create complications for self-employed people, whose net income depends on business expenses and deductions that vary year to year. Gross income provides a clearer, more uniform way to measure financial capacity across all types of earners.

Frequently Asked Questions

If I take a pay cut, will my Medicare premiums go down right away?

Not automatically. Your premiums are based on your tax return from two years prior. If you experience a significant income drop, you can report it to Social Security and request a recalculation. Otherwise, you will see the change reflected in your premiums once your new tax return is processed — typically the following year.

Does my spouse's income count toward my Medicare premiums?

Only if you file a joint tax return. If you file jointly, Medicare combines both incomes to calculate IRMAA. If you file separately, only your individual income counts, but the income thresholds for extra premiums are much lower for people who file separately, often resulting in higher premiums overall.

What if I have no income but I have savings?

Savings and assets do not count toward IRMAA. Only income — earnings, interest, dividends, and similar sources — matters. You can have substantial savings and still owe standard Medicare premiums if your income is below the IRMAA thresholds.

Can I reduce my gross income to lower my Medicare premiums?

Some strategies, such as contributing to a traditional IRA or a 401(k), reduce your taxable income and may lower your IRMAA. However, Medicare uses MAGI, which includes some income that is not subject to tax. Speak with a tax professional or financial advisor about strategies that fit your situation.

When do the new income thresholds for IRMAA take effect?

IRMAA thresholds are adjusted each January based on inflation. Your premiums reflect the thresholds in effect for that calendar year. You can find the current year's thresholds on the Medicare website or by calling Social Security.