IRMAA glossary: the words on your Social Security letter
By Elder PaperworkUpdated
Short answer
A “new initial determination” is a new Social Security decision on IRMAA, based on other tax information.
It doesn’t need an appeal. It is how a life-changing event lowers your IRMAA.
Below: the other terms you’ll meet, in plain English.
Sources: POMS HI 01120.001, June 2026; POMS HI 01140.001, June 2026. Read November 4, 2026.
Key facts
What does IRMAA mean?
Income-related monthly adjustment amount. An extra amount on Part B and Part D premiums when income is higher.
What is MAGI?
Modified adjusted gross income. For IRMAA: AGI (Form 1040, line 11) plus tax-exempt interest (line 2a).
What is a life-changing event?
One of 8 events that can lower your income: marriage, divorce, death of a spouse, work stoppage or reduction.
Also: loss of income property, loss of pension income, or an employer settlement.
What is a new initial determination?
A new Social Security decision using a more recent or more accurate tax year. It is not an appeal.
What is a non-qualifying event?
A one-time income jump, like a capital gain or an IRA conversion. It can’t lower IRMAA.
See what you could save, before you pay.
Check my savingsWhat do PY-1 and PY-2 mean?
Premium year minus 1 or 2. For 2026, PY-2 is tax year 2024 and PY-1 is 2025.
What is a predetermination notice?
A notice of what Social Security plans to do. It is not a determination and has no appeal rights.
What is a reconsideration?
The first level of appeal, asked within 60 days of receiving the notice. Form SSA-561-U2.
What is a representative payee?
Social Security’s rules say a representative payee can ask for a new decision or a reconsideration for the beneficiary.
Questions
Is a new initial determination an appeal?
No. It is a new decision, without an appeal.
What does PY-2 mean?
Premium year minus 2. For 2026, tax year 2024.
Does a predetermination notice have appeal rights?
No. It is not a determination.