IRS Notice Glossary: What the Terms Actually Mean
An IRS notice glossary translates the vocabulary in letters and audits, such as deficiency, assessment, lien, levy, abatement, Appeals and transcript, into plain language so you can tell what the IRS is proposing, what it is asking you to do, and what the next step is.
Reading the notice itself
Start with the paperwork basics. The terms below show up on almost every letter, and knowing them makes the rest easier to follow.
- Notice number: the CP or LTR code printed in the upper right corner of the letter. You can search the IRS website for that number to find a page explaining the notice.
- Response date: the due date on the notice. Replying by that date is how you keep appeal rights, so treat it as the clock that matters.
- Proposed change: what the IRS thinks should be different on your return. A proposal is not the same as a bill.
- Notice of deficiency: a formal notice proposing additional tax. It carries a firm deadline to ask the Tax Court to review it, 90 days (150 if addressed outside the U.S.), and the notice shows the last day. A reply to the IRS does not extend that deadline.
- Statute of limitations (assessment): the time limit for the IRS to assess additional tax, generally three years from the date you file, longer in some cases.
Money terms: assessment, balance and interest
Assessment is the point at which the IRS formally records tax as owed and can bill you for it. For a deficiency, the IRS generally cannot assess until the notice has been mailed, the 90 or 150 days has run, and any Tax Court case is final. After assessment, interest accrues and penalties may apply, so a balance can grow while you decide what to do.
- Deficiency: the additional tax the IRS says you owe beyond what was reported.
- Interest: a charge on unpaid tax. The rate changes, so check the IRS page for the current figure rather than relying on a number in an old article.
- Payment plan (installment agreement): an arrangement to pay over time, which you can often set up online.
Penalty terms: abatement and reasonable cause
Abatement means the IRS removes or reduces a penalty. It does not erase the underlying tax, and interest on a removed penalty is adjusted automatically.
- Reasonable cause: relief the IRS may give when you acted with ordinary care and in good faith. It is decided case by case. Examples the IRS gives include a disaster, serious illness, or being unable to obtain records; relying on a professional or simply lacking funds generally does not qualify on its own.
- First-time abatement: relief for certain late-filing, late-payment or late-deposit penalties when your recent filing and payment history is clean. The IRS describes a move toward an automatic version for newer tax years, so check its penalty relief page for status.
- Form 843: a claim form used to request penalty abatement in writing if a phone call does not resolve it.
Disagreeing and appealing
These are the places a disagreement can go, from least to most formal.
- Appeals: the Independent Office of Appeals, a part of the IRS separate from the examiners and collectors. Using it is optional and does not waive your right to go to court.
- Small case request: a short written request for an appeal, generally available when the tax and penalties for each period in the letter are $25,000 or less. Larger amounts call for a formal written protest.
- Protest: a written statement listing the issues you dispute, the facts, and the law you rely on, signed under penalties of perjury.
- Tax Court: an independent court. Smaller disputes may qualify for a simplified small tax case procedure, with a limit that is $50,000 or less for many case types; check the Court's current guidance.
Collection terms: lien, levy and CDP
People often mix up lien and levy. A lien is the government's legal claim against your property for unpaid tax; it secures the debt without taking anything. A levy is the actual seizure of property, such as money in a bank account or part of a paycheck. People often say wage garnishment, while IRS materials use the word levy.
- Notice of Federal Tax Lien: a public filing that alerts creditors to the lien and can affect credit.
- Release, withdrawal, discharge, subordination: different remedies for a lien, each with different effects.
- Final notice of intent to levy: a notice that comes with a right to a hearing. The deadline is printed on it and is generally about 30 days.
- Collection Due Process (CDP) hearing: the hearing you can request with Appeals after a lien or levy notice, using Form 12153.
- Equivalent hearing: a later request that may still be heard, but without court review.
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Start your response letterFrequently asked questions
What is the difference between a lien and a levy?
A lien is a legal claim on your property that secures a tax debt. A levy is the actual seizure of property or money, such as funds in a bank account or wages, to pay the debt.
Does abatement erase the tax I owe?
No. Abatement refers to removing or reducing a penalty. The underlying tax remains, although interest on a penalty that is removed is adjusted automatically.
Is a proposed change the same as a bill?
No. A proposal, such as in a CP2000 or a notice of deficiency, says what the IRS thinks should change. You usually have a chance to agree or respond before an amount is assessed and billed.
Where do I find my notice number?
Look in the upper right corner of the letter for a code beginning with CP or LTR. You can search the IRS website for that code to read the IRS explanation of that notice.
Can software explain what my specific notice means?
IRS Audit Defense Pro is software that helps you organize facts and draft a response letter you review yourself. It is not a law firm, CPA or enrolled agent and does not give legal or tax advice.