2026 Adjustments to Medicare Parts A, B, and D: A Technical Review of Premiums and IRMAA Calculations
On November 14, 2025, the Centers for Medicare & Medicaid Services (CMS) released the finalized amounts for premiums, deductibles, and coinsurance under the Medicare Part A and Part B programs for the 2026 calendar year, concurrently announcing the Medicare Part D income-related monthly adjustment amounts (IRMAA). This technical brief reviews the statutory context and the specific figures relevant to client planning for 2026, focusing particularly on the impact of modified adjusted gross income (MAGI) thresholds on Part B and Part D premiums.
Medicare Part B Premium and Income-Related Monthly Adjustment Amounts
Part B coverage encompasses physicians’ services, outpatient hospital services, durable medical equipment, and other medical and health services not covered by Part A. The annual determination of the Part B premium, deductible, and coinsurance rates is mandated by provisions of the Social Security Act.
The standard monthly premium for Medicare Part B enrollees in 2026 is $202.90, reflecting an increase of $17.90 from the 2025 premium of $185.00. The annual deductible for all Part B beneficiaries for 2026 is set at $283, an increase of $26 from the 2025 deductible of $257.
CMS attributes the increase in the 2026 Part B standard premium and deductible mainly to projections of price changes and assumed utilization increases consistent with historical trends. CMS specifically noted a mitigating factor in the rate calculation: due to changes finalized in the 2026 Physician Fee Schedule Final Rule, spending on skin substitutes is expected to drop by 90%. Had the Trump Administration not taken action to address this previously unprecedented spending on skin substitutes, the Part B premium increase would have been approximately $11 higher per month.
Since 2007, the Part B monthly premium has been subject to a beneficiary's income, impacting roughly 8% of Medicare Part B participants.
Part B Income-Related Monthly Adjustment Amounts (IRMAA)
The 2026 Part B total monthly premiums for high-income beneficiaries with full Part B coverage are structured based on MAGI, as follows:
| Beneficiaries Filing Individual Tax Returns (MAGI) | Beneficiaries Filing Joint Tax Returns (MAGI) | IRMAA | Total Monthly Premium Amount |
|---|---|---|---|
| < $109,000 | < $218,000 | $0.00 | $202.90 |
| >$109,000 and < $137,000 | >$218,000 and < $274,000 | $81.20 | $284.10 |
| >$137,000 and < $171,000 | >$274,000 and < $342,000 | $202.90 | $405.80 |
| >$171,000 and < $205,000 | >$342,000 and < $410,000 | $324.60 | $527.50 |
| >$205,000 and <$500,000 data-preserve-html-node="true" | >$410,000 and <$750,000 data-preserve-html-node="true" | $446.30 | $649.20 |
| > $500,000 | > $750,000 | $487.00 | $689.90 |
For high-income beneficiaries who are married, lived with their spouse at any time during the taxable year, but file a separate tax return, the premiums for full Part B coverage are tiered differently:
| Beneficiaries Filing Separate Tax Returns (MAGI) | IRMAA | Total Monthly Premium Amount |
|---|---|---|
| < $109,000 | $0.00 | $202.90 |
| >$109,000 and <$391,000 data-preserve-html-node="true" | $446.30 | $649.20 |
| > $391,000 | $487.00 | $689.90 |
Part B Immunosuppressive Drug Coverage Only
Beginning in 2023, certain individuals whose full Medicare coverage ceased 36 months after a kidney transplant can elect to maintain Part B coverage for immunosuppressive drugs by paying a premium, provided they lack certain other insurance. The standard premium for this specialized coverage is $121.60 for 2026.
The Part B total premiums for high-income beneficiaries with immunosuppressive drug coverage only are set forth below:
| Beneficiaries Filing Individual Tax Returns (MAGI) | Beneficiaries Filing Joint Tax Returns (MAGI) | IRMAA | Total Monthly Premium Amount |
|---|---|---|---|
| < $109,000 | < $218,000 | $0.00 | $121.60 |
| >$109,000 and < $137,000 | >$218,000 and < $274,000 | $81.10 | $202.70 |
| >$137,000 and < $171,000 | >$274,000 and < $342,000 | $202.70 | $324.30 |
| >$171,000 and < $205,000 | >$342,000 and < $410,000 | $324.30 | $445.90 |
| >$205,000 and <$500,000 data-preserve-html-node="true" | >$410,000 and <$750,000 data-preserve-html-node="true" | $445.90 | $567.50 |
| > $500,000 | > $750,000 | $486.50 | $608.10 |
For those with immunosuppressive drug coverage only who file separately while living with their spouse, the 2026 premiums are:
| Beneficiaries Filing Separate Tax Returns (MAGI) | IRMAA | Total Monthly Premium Amount |
|---|---|---|
| < $109,000 | $0.00 | $121.60 |
| >$109,000 and <$391,000 data-preserve-html-node="true" | $445.90 | $567.50 |
| > $391,000 | $486.50 | $608.10 |
Medicare Part D Income-Related Monthly Adjustment Amounts (IRMAA)
The Part D monthly premium has been income-based since 2011. Like Part B IRMAA, these adjustments affect about 8% of Part D beneficiaries. The IRMAA is paid in addition to the standard Part D premium (which varies by specific plan) and is either deducted from Social Security benefits or paid directly to Medicare.
The 2026 Part D income-related monthly adjustment amounts for standard filers are:
| Beneficiaries Filing Individual Tax Returns (MAGI) | Beneficiaries Filing Joint Tax Returns (MAGI) | Income-related Monthly Adjustment Amount |
|---|---|---|
| < $109,000 | < $218,000 | $0.00 |
| >$109,000 and < $137,000 | >$218,000 and < $274,000 | $14.50 |
| >$137,000 and < $171,000 | >$274,000 and < $342,000 | $37.50 |
| >$171,000 and < $205,000 | >$342,000 and < $410,000 | $60.40 |
| >$205,000 and <$500,000 data-preserve-html-node="true" | >$410,000 and <$750,000 data-preserve-html-node="true" | $83.30 |
| > $500,000 | > $750,000 | $91.00 |
For Part D beneficiaries who are married, lived with their spouse at any time during the taxable year, but file a separate return, the 2026 IRMAA is:
| Beneficiaries Filing Separate Tax Returns (MAGI) | Income-related Monthly Adjustment Amount |
|---|---|
| < $109,000 | $0.00 |
| >$109,000 and <$391,000 data-preserve-html-node="true" | $83.30 |
| > $391,000 | $91.00 |
Medicare Part A Premiums and Deductibles
Medicare Part A generally covers inpatient hospital, skilled nursing facility, and hospice care. Notably, approximately 99% of Medicare beneficiaries do not pay a Part A premium, having satisfied the requirement of at least 40 quarters of Medicare-covered employment.
Part A Deductibles and Coinsurance: The Medicare Part A inpatient hospital deductible for 2026 is $1,736, an increase of $60 from the 2025 amount of $1,676. This deductible covers the beneficiary’s share of costs for the first 60 days of Medicare-covered inpatient hospital care in a benefit period.
Part A coinsurance amounts have also been revised for 2026:
- Daily hospital coinsurance for the 61st through 90th day in a benefit period is $434 ($419 in 2025).
- Daily hospital coinsurance for lifetime reserve days is $868 ($838 in 2025).
- Daily coinsurance for skilled nursing facilities (days 21 through 100) is $217.00 ($209.50 in 2025).
Voluntary Part A Enrollment Premiums: Individuals aged 65 and older with fewer than 40 quarters of coverage may voluntarily enroll in Part A by paying a monthly premium.
- Those with at least 30 quarters of coverage (or married to someone with at least 30 quarters) may purchase Part A at a reduced monthly premium rate, which will be $311 in 2026 (a $26 increase from 2025).
- Uninsured aged individuals with fewer than 30 quarters of coverage must pay the full premium, which will be $565 a month in 2026 (a $47 increase from 2025).
These 2026 rates and MAGI thresholds, derived from CMS final notices (CMS-8089-N, CMS-8090-N, CMS-8091-N), are essential inputs for tax professionals engaged in year-end planning, particularly for optimizing MAGI to avoid or mitigate IRMAA liabilities.
Prepared with assistance from NotebookLM.