2026 Medicare Part B and Part D IRMAA Calculator
Enter the modified adjusted gross income and filing status used by Medicare to see both 2026 income-related surcharges, the full monthly premiums, and how close the return sits to the next income tier.
One income tier controls two separate Medicare charges
Part B IRMAA and Part D IRMAA belong in one calculation because Social Security uses the same modified adjusted gross income, filing-status table, and premium year to assign both. The dollar add-ons are different, and the way they appear on a bill is different, but the income tier is shared. A beneficiary enrolled in both parts can cross one threshold and see both monthly costs change at once.
The result starts with the standard 2026 Part B premium of $202.90, then adds the Part B income-related monthly adjustment amount. Part D begins with the premium charged by the selected drug plan, then adds the separate Part D IRMAA amount. Part D IRMAA does not buy a richer plan and is not paid to the drug insurer in the ordinary way. Medicare generally collects it through a Social Security deduction or direct bill.
Part B ticket
The result displays the income-related surcharge and the full standard Part B monthly premium. It does not include a late-enrollment penalty, an income-related amount for immunosuppressive-drug-only coverage, or a Medicare Advantage plan premium.
Part D ticket
The result adds the official 2026 Part D IRMAA to the plan premium entered above. A Part D late-enrollment penalty is a different calculation based on uncovered months and the national base beneficiary premium.
Which tax return supplies 2026 IRMAA income?
Medicare usually looks back two years because that is the latest federal return information available when premiums are set. For 2026 premiums, that generally means the 2024 federal return. Social Security can use older data if the expected return is unavailable, or more recent information after an approved new initial determination. The premium notice identifies the tax year and filing status actually used; enter those facts rather than assuming the normal lookback always applied.
IRMAA modified adjusted gross income is not every “MAGI” used elsewhere in federal tax law. For this purpose, it is generally adjusted gross income plus tax-exempt interest. On a Form 1040, that commonly means starting with line 11 and adding line 2a. A municipal-bond distribution can therefore affect Medicare premiums even though it is excluded from regular federal taxable income. Do not substitute taxable income, gross income, or Social Security’s benefit amount.
Filing status controls the threshold table. Single, head of household, and qualifying surviving spouse use the individual table for these CMS amounts. Married filing jointly uses thresholds that are generally twice the individual values. A married person who filed separately and lived with a spouse at any time during the tax year uses a compressed special table. A married-separate filer who lived apart for the entire year may not belong in that compressed category; verify the notice and Social Security rule.
The 2026 thresholds are cliffs, not gradual phase-ins
IRMAA does not increase by a few cents for every extra dollar of income. Each tier assigns a fixed monthly amount. At an exact upper boundary, the beneficiary remains in the lower tier where CMS says “less than or equal to.” The next ordinary tier starts above that figure. The highest tier begins at $500,000 for an individual return and $750,000 for a joint return, so those exact amounts are already in the highest tier.
| 2024 MAGI used for 2026 | Joint-return MAGI | Part B IRMAA | Part D IRMAA |
|---|---|---|---|
| $109,000 or less | $218,000 or less | $0.00 | $0.00 |
| Over $109,000 through $137,000 | Over $218,000 through $274,000 | $81.20 | $14.50 |
| Over $137,000 through $171,000 | Over $274,000 through $342,000 | $202.90 | $37.50 |
| Over $171,000 through $205,000 | Over $342,000 through $410,000 | $324.60 | $60.40 |
| Over $205,000 but below $500,000 | Over $410,000 but below $750,000 | $446.30 | $83.30 |
| $500,000 or more | $750,000 or more | $487.00 | $91.00 |
For married filing separately after living with a spouse, the special 2026 table has only three effective levels: no surcharge through $109,000, the fifth-tier amounts above $109,000 but below $391,000, and the highest amounts at $391,000 or more. That rule is why the filing-status choice cannot be handled merely by dividing the joint thresholds in half.
A life-changing event can replace the old return
A retirement-year income drop does not automatically change an IRMAA notice. If Social Security used a high-income return from two years earlier, the beneficiary can request a new initial determination after a qualifying life-changing event and a reduction in modified adjusted gross income. Form SSA-44 lists marriage, divorce or annulment, death of a spouse, work stoppage, work reduction, loss of income-producing property, loss of pension income, and an employer settlement payment.
Identify the income year, MAGI, status, premium year, and appeal or reconsideration instructions.
Match the real circumstance to an SSA-44 life-changing event; an ordinary investment loss is not automatically enough.
Provide AGI plus tax-exempt interest for the more recent or anticipated tax year and support the income reduction.
Confirm the effective month and preserve Social Security’s determination with later tax-return evidence.
An amended tax return, an IRS error, or missing tax data can follow a different correction route. The calculator cannot decide whether evidence is sufficient or which month a revised amount begins. It does show the dollar difference between tiers so the beneficiary can understand what is at stake before contacting Social Security.
Example: a single beneficiary with $180,000 of MAGI
Assume the 2026 notice uses an individual return with $180,000 of 2024 IRMAA MAGI. That amount is above $171,000 and not above $205,000, so it falls in tier 4. The monthly Part B IRMAA is $324.60. Adding the $202.90 standard premium produces a $527.50 Part B monthly amount.
Part D IRMAA is $60.40 in the same tier. If the selected plan premium is $50, the combined drug-coverage charge is $110.40. A person enrolled in both parts would therefore model $637.90 per month, or $7,654.80 for twelve months. Of that annual total, $4,620 is IRMAA and the remainder is the standard Part B plus entered plan premium.
The return has $25,000 before reaching the $205,000 upper edge. Remaining below an edge should never justify an uneconomic tax move by itself. A Roth conversion, realized capital gain, charitable distribution strategy, tax-exempt bond interest, and filing-status choice can have consequences far beyond Medicare. Model the full federal and state tax result, not only the surcharge.
Planning details that commonly change the answer
- Both spouses may pay. A joint return assigns the tier, but each Medicare-enrolled spouse is charged an individual Part B and Part D IRMAA. Run the premium count for each enrolled person rather than treating the displayed combined result as a household maximum.
- Partial-year enrollment changes annual cost. The calculator annualizes twelve current monthly premiums. A new enrollee, disenrollee, midyear reconsideration, or retroactive correction needs a month-by-month total.
- Withholding does not change MAGI. Federal tax withheld from a pension or Roth conversion is a payment, not an income reduction. Paying more estimated tax will not move the return to a lower IRMAA tier.
- Qualified charitable distributions can matter differently. A properly reported QCD is generally excluded from AGI, while an ordinary IRA withdrawal followed by a charitable gift may increase AGI even when an itemized deduction offsets taxable income.
- Thresholds change annually. This calculator uses the official 2026 table. Do not reuse it for 2025 or forecast it as the final 2027 schedule.
Questions Medicare beneficiaries ask about IRMAA
If our joint return crosses a tier, is the surcharge split between spouses?
No. The joint MAGI determines the tier, but each spouse who has Part B pays that tier’s Part B amount, and each spouse with Part D pays that tier’s Part D amount. A couple with both parts can therefore have twice the individual monthly surcharges shown for one beneficiary.
Does a Roth IRA conversion count in IRMAA MAGI?
The taxable portion of a conversion generally enters AGI and can affect the later IRMAA year. Nontaxable basis does not become taxable merely because it is converted. Because IRMAA usually looks back two years, a 2024 conversion can affect 2026 premiums.
Why did Medicare use tax-exempt municipal-bond interest?
The Medicare IRMAA definition generally adds tax-exempt interest to adjusted gross income. The interest may remain exempt from regular federal income tax while still increasing the MAGI that assigns a Part B and Part D surcharge tier.
Can I appeal merely because the premium is expensive?
Cost alone does not change the statutory table. A request usually needs an error, amended return, qualifying life-changing event with reduced income, or another recognized basis. Follow the deadline and instructions on the Social Security notice.
Is Part D IRMAA included in the premium quoted by my drug plan?
Usually no. The plan quotes its own premium, while Medicare collects the income-related adjustment separately. The calculator adds the entered plan premium and official Part D IRMAA so the monthly cash cost is visible in one place.
References
Centers for Medicare & Medicaid Services. 2026 Medicare Parts A & B Premiums and Deductibles. Social Security Administration. Request to Lower an Income-Related Monthly Adjustment Amount (IRMAA). Social Security Administration. Form SSA-44, Medicare Income-Related Monthly Adjustment Amount—Life-Changing Event.