What is IRMAA, and how can a pension or lump sum raise my Medicare premiums?

Rules checked October 18, 2026, against cms.gov and ssa.gov

How IRMAA is figured

Social Security decides who pays IRMAA, using income information from the IRS. Three rules drive everything (SSA: Medicare premiums, rules for higher-income beneficiaries):

• It uses modified adjusted gross income (MAGI). For IRMAA, that is your adjusted gross income plus tax-exempt interest income. Pensions, wages, taxable TSP, 457 and IRA withdrawals, the taxable part of Social Security and capital gains all go into adjusted gross income.
• It looks back two years. Social Security uses the most recent federal tax return the IRS provides. For 2026 premiums, that is usually your 2024 return. If only your 2023 return is on file, Social Security uses that and updates it later.
• It is decided one year at a time. Each year's IRMAA depends on the income for that year's lookback. A one-time spike affects one year of premiums, not the rest of your life.

The thresholds work like cliffs. Going $1 over a bracket line means paying the full extra amount for that bracket for the whole year.

If you get Social Security, the extra amounts are taken out of your monthly check, even if you pay your Part D plan premium another way. If your check is too small or you don't get one yet, you get a separate bill.

2026 Part B amounts

The standard 2026 Part B premium is $202.90 a month. With IRMAA, total Part B premiums are (CMS: 2026 Medicare Parts A and B premiums and deductibles):

For married people filing separately who lived with their spouse at any time during the year, the brackets are much tighter: $202.90 up to $109,000, $649.20 from $109,001 to under $391,000, and $689.90 at $391,000 or more.

For a married couple where both are on Medicare, each spouse pays the amount shown, based on their joint income.

2026 Part D amounts

For Part D, IRMAA is an extra amount added to whatever your drug plan charges. The brackets match Part B (CMS fact sheet):

If you get drug coverage through a retiree plan that is not a Part D plan, Part D IRMAA doesn't apply to you. If your retiree program enrolls you in a Medicare Part D or Medicare Advantage plan with drug coverage, it can.

What can push a public retiree over

Most public retirees live well under $109,000 of income. The risk comes from one-time spikes and from the two-year lookback catching your last working years:

• Your last full year of salary. If you retire at 64 or 65, the tax return Social Security uses for your first Medicare years may show a full salary, possibly plus a payout of unused vacation leave.
• Pension plus salary in the same year. Someone who retires midyear may have half a year of salary and half a year of pension on one return.
• Lump sums from savings. A large withdrawal from the TSP, a 457 or 403(b), or an IRA counts in full as income for that year (unless it is rolled over or comes from Roth money). An Oregon PERS IAP account taken as a lump sum and not rolled over is a common example.
• Roth conversions and large capital gains from selling property or investments.
• Higher taxable Social Security, since up to 85% of benefits counts in adjusted gross income (see Are Social Security benefits taxed?).

Lowering IRMAA after you retire (form SSA-44)

If your income has dropped because of a life-changing event, you don't need to appeal. You can ask Social Security for a new decision using your newer income. The life-changing events are a fixed list (SSA POMS HI 01120.005):

• Death of a spouse
• Marriage
• Divorce or annulment
• Work reduction (you or your spouse cut back hours)
• Work stoppage (you or your spouse retired or stopped working)
• Loss of income-producing property, from a disaster or event beyond your control
• Loss of an employer pension (for example, a plan ending or being reorganized)
• A settlement payment from a current or former employer because of closure, bankruptcy or reorganization

Retiring is the most common qualifying event for public employees. But the list is exclusive. Social Security says one-time income spikes, such as capital gains from selling property, IRA conversions or cashing bonds, are not life-changing events. So if the high income came from a lump-sum withdrawal you chose to take, SSA-44 generally won't help. Planning the timing of withdrawals is the only real fix.

How to file (SSA: Request to lower IRMAA):

1. Fill out form SSA-44, Medicare Income-Related Monthly Adjustment Amount: Life-Changing Event. You can submit it online through a my Social Security account, or fax or mail it to a Social Security office. You can also call 1-800-772-1213.
2. Include proof of the event, such as a letter from your employer or pension system showing your retirement date.
3. Give your estimated income for the year with the lower income. If you filed a federal return for that year, include a signed copy.

If Social Security used the wrong income (for example, an IRS error or an amended return), you also don't need an appeal. Contact Social Security with the correct information. If you disagree with a decision, you can appeal online or file a request for reconsideration on form SSA-561-U2.

2027 amounts

CMS has not yet announced 2027 Part B premiums or IRMAA brackets as of October 18, 2026. They usually come out in the fall, often in November (the 2026 figures were released November 14, 2025). Social Security says 2027 Medicare premium amounts will appear in the my Social Security Message Center starting in late November (SSA: 2027 COLA announcement). For 2027, Social Security will generally use 2025 tax returns. We'll add the 2027 tables here when they are published.

What to do next

1. Look at the return two years before each Medicare year. Your 2025 return generally sets 2027 premiums, and 2026 sets 2028.
2. Plan big withdrawals. Spreading a TSP, 457 or IAP withdrawal over several years, or rolling it over, can keep income under a bracket line.
3. File SSA-44 as soon as you get an IRMAA notice after retiring. Keep your retirement letter from PERS, DRS, OPM or your employer handy.
4. Check when you start Medicare. See our guide When should I sign up for Medicare?

General information, not advice. We aren't part of CMS or the Social Security Administration. For your own IRMAA decision, contact Social Security at 1-800-772-1213, and ask a tax professional before a large withdrawal.