What determines your Medicare premium
Your Medicare Part B and Part D premiums are based on your income from two years ago — specifically, your Modified Adjusted Gross Income (MAGI) from your tax return. If your income was higher two years ago, you pay more now. If your income dropped — through retirement, job loss, or a major life change — you can report that change and potentially lower your premium right away.
Part A (hospital insurance) has no monthly premium for most people because you or your spouse paid Medicare taxes while working. Part B (doctor visits and outpatient care) and Part D (prescription drugs) both use the income-based system, and they can increase significantly if your income crosses certain thresholds.
The income brackets and premium amounts change each year. Your premium letter, which arrives in December, shows the exact amount you will pay starting in January and explains which income year triggered it.
Key Takeaways
- Medicare uses your income from two years prior to set your Part B and Part D premiums, so a recent drop in income may not show up until next year.
- Income thresholds trigger higher premiums in steps — crossing one threshold does not mean you pay the top rate, only a higher rate for that income bracket.
- If you had a major life event (retirement, death of a spouse, job loss), you can report it to Social Security and request a premium reduction based on current income.
- Part A has no premium for most people; Part B and Part D premiums rise together as income increases.
- Your premium letter in December shows your 2025 amount and which tax year determined it, so you can plan ahead.
How income brackets work for Part B premiums
Medicare divides people into income brackets, and each bracket has its own Part B premium. For 2024, a single person with income under $91,000 pays the standard premium (around $164.90 per month, though this changes yearly). Someone with income between $91,000 and $114,000 pays more. Someone between $114,000 and $142,000 pays even more. The brackets continue upward, and the highest earners pay roughly triple the standard rate.
The key point: you do not jump to the top rate just by crossing one threshold. If your income is $115,000, you pay the rate for the $114,000–$142,000 bracket, not the rate for people earning $500,000. Each bracket has its own premium amount, and you pay only the one that matches your income.
These thresholds and amounts are set by law and change each year. Your December premium letter will show you which bracket you fall into and why.
Part D premiums and income-related adjustments
Part D (prescription drug coverage) works the same way. Your plan's base premium is set by the insurance company, but if your income is above a certain threshold, Medicare adds an Income-Related Monthly Adjustment Amount (IRMAA) on top. Like Part B, this adjustment increases in steps as income rises.
If you are married and file jointly, Medicare uses your combined household income. If you are single, it uses your individual income. The thresholds for Part D adjustments are different from Part B thresholds, so you may see an adjustment on one but not the other — or adjustments on both at different rates.
Your Part D plan letter (from your insurance company) and your Medicare premium letter (from Social Security) will both show these amounts separately, so you can see exactly what you are paying and why.
What counts as income for Medicare premiums
Medicare uses your Modified Adjusted Gross Income (MAGI) from your federal tax return. This includes wages, self-employment income, interest, dividends, rental income, Social Security benefits (even if not taxed), and distributions from retirement accounts. It does not include certain things like Supplemental Security Income (SSI) or some veterans' benefits.
If you are married and file jointly, both spouses' income counts toward the household total, even if only one of you is on Medicare. If you file separately, each person's income is counted separately, but filing separately usually results in a higher MAGI calculation anyway.
The IRS and Social Security share information, so the income they have on file is what Medicare uses. You do not have to report it yourself — it is pulled automatically from your tax return.
Reporting a life change to lower your premium now
If you had a major life event in the past year — retirement, death of a spouse, job loss, or a significant drop in income — you can report it to Social Security and request that your premium be recalculated based on your current income instead of income from two years ago. This is called a life-changing event appeal.
You will need to document the event: a termination letter from your employer, a death certificate, divorce papers, or a recent tax return showing lower income. Call Social Security at 1-800-772-1213 (TTY 1-800-325-0778) or visit your local Social Security office. You can also contact Medicare directly at 1-800-MEDICARE (1-800-633-4227).
Social Security will review your case and, if approved, adjust your premium retroactively to the month after the event occurred. This can take several weeks, so it is worth doing as soon as you know your income has dropped.
Why your premium increased from last year
Your premium went up for one of three reasons: (1) the standard Medicare premium increased across the board, (2) your income from two years ago was higher than the year before, or (3) you crossed into a higher income bracket. Your December premium letter will tell you which one.
If you see a large jump and you know your income has actually dropped, do not assume the letter is wrong. Remember that the premium is based on old income. If you retired last year, your 2025 premium is still based on 2023 income — your 2026 premium will reflect your retirement year. In the meantime, report the life change to Social Security to get relief sooner.
If your income has stayed the same or increased, the jump is likely the annual increase to the standard premium, which Congress and the Centers for Medicare & Medicaid Services (CMS) set each fall.
Part A premiums for people without work history
Most people do not pay a Part A premium because they or their spouse paid Medicare taxes for at least 10 years (40 quarters) while working. But if you did not work that long, you may have to pay a monthly Part A premium to have hospital coverage.
Part A premiums are not income-based — they are a flat amount set by law each year. For 2024, the premium ranges from around $278 to $556 per month depending on how many quarters of work history you have. This amount does not change based on your income; it is the same for everyone in your situation.
If you are unsure whether you owe a Part A premium, your Medicare Summary Notice (sent each year) or your premium letter will show it. You can also call Social Security or Medicare to check your work history.
Frequently Asked Questions
Why is my 2025 premium based on 2023 income when I retired in 2024?
Medicare uses a two-year lag so it has time to collect tax data from the IRS. Your 2026 premium will be based on 2024 income (your first full retirement year), and it will be lower. If you need relief now, report your retirement to Social Security and request a life-changing event adjustment — they can recalculate your premium based on current income.
If I am married and my spouse is not on Medicare yet, does their income count toward my premium?
Yes, if you file taxes jointly. Medicare counts combined household income for married couples filing jointly, even if only one spouse is enrolled. If you file separately, each person's income is counted separately — but filing separately usually increases your MAGI calculation, so it is rarely worth it.
Can I appeal my premium if I think it is wrong?
Yes. If you believe Social Security or Medicare used the wrong income, you can request a reconsideration. Call 1-800-MEDICARE or visit your local Social Security office with a copy of your tax return or other income documentation. They will review your case and correct it if there was an error.
What happens to my premium if I go back to work after retirement?
Your premium will not change until two years after your income increases. If you return to work in 2025, your 2025 and 2026 premiums are based on 2023 income (before you went back). Your 2027 premium will reflect your 2025 work income. If the increase is significant, you can report it to Social Security and request an adjustment based on current income.
Do I pay income tax on top of my Medicare premium?
No. Your Medicare premium is deducted from your Social Security check (or billed separately if you do not receive Social Security). It is not an income tax — it is a monthly insurance payment. You do not deduct it on your tax return.