Tax Resolution Basics
Tax Resolution Terms Glossary: Every Term, Plainly (2025)
The short answer: this tax resolution terms glossary defines every word you'll meet while dealing with IRS debt — liens, levies, CSED, Offer in Compromise, Currently Not Collectible, and more — in plain English. Use it to decode your notice, then act before deadlines turn into enforcement.
If you're holding an IRS letter and half the words look like a foreign language, you're in the right place. The IRS writes in acronyms and legal terms, and tax relief companies pile on more. Below is a calm, plain-English tax resolution glossary so you can understand exactly what's happening and what your choices are. We've grouped the terms the way they actually come up — notices first, then collection words, then the programs that fix things.
IRS notice and letter terms
These are the things that show up in your mailbox. Real IRS notices arrive by postal mail and have a code in the top or bottom corner.
- CP14 — the IRS's first bill for unpaid taxes. It says you owe and gives you about 21 days to pay or set something up. See our CP14 notice guide for the full walkthrough.
- CP501 / CP503 / CP504 — reminder notices that follow the CP14 if you don't respond. CP504 is a Notice of Intent to Levy and is the first one with real teeth.
- LT11 / Letter 1058 — the Final Notice of Intent to Levy. After 30 days, the IRS can garnish wages and seize bank accounts. This notice carries your right to a hearing.
- CP2000 — not a bill and not an audit. It's a proposed change to your return because income reported to the IRS (a W-2 or 1099) doesn't match what you filed.
- Notice of Deficiency (CP3219A / "90-day letter") — a formal notice that the IRS plans to assess more tax. It gives you 90 days to petition the U.S. Tax Court.
- Substitute for Return (SFR) — a return the IRS files for you when you don't file, usually with no deductions in your favor. You can replace it by filing your own.
Not sure a letter is even real? Our guide on how to tell if an IRS letter is real walks through the scam checks.
Collection and enforcement terms
These describe what the IRS can do to collect a debt — and the deadlines that protect you.
- Assessment — the moment the IRS officially records that you owe a specific amount. The collection clock starts here.
- Lien — a legal claim against your property that secures the debt. It doesn't take anything, but it can block a sale or loan.
- Levy — the actual seizure of money or property: a bank account, a paycheck, a tax refund. After a bank levy, the bank holds the funds for 21 days before sending them to the IRS — your one window to act.
- Garnishment — a levy on your wages. The IRS leaves you a protected amount and takes the rest each pay period until the debt is paid or the levy is released.
- CSED (Collection Statute Expiration Date) — the date the IRS's 10-year window to collect runs out. Read more in our guide to how long the IRS can collect back taxes.
- Tolling — events that pause the 10-year clock, like filing an Offer in Compromise, bankruptcy, or a collection appeal. The time adds back on.
- Revenue Officer — a real IRS employee assigned to collect harder cases, sometimes in person. Different from a revenue agent (who audits) and very different from a scammer.
- CDP Hearing (Collection Due Process) — your right to appeal a levy or lien before the IRS acts, requested on Form 12153.
Penalty and interest terms
Most tax debts grow because of these. Knowing the difference helps you stop the bleeding.
- Failure-to-file penalty — charged when you file late. It's 5% of unpaid tax per month, capped at 25%. The expensive one.
- Failure-to-pay penalty — charged when you file but don't pay. It's 0.5% per month, also capped at 25%. The difference between failure-to-file and failure-to-pay penalties is why you should always file on time, even broke.
- Accuracy-related penalty — a 20% penalty when you significantly understate tax or are negligent.
- Interest — added to your unpaid balance daily and compounded. It's set by law and is rarely waived on its own.
- Abatement — removing a penalty. First-time abatement applies if you have a clean recent history; reasonable-cause relief applies for illness, disaster, or events beyond your control.
Confused by the words on your letter?
Send us a photo of your notice. An experienced tax professional will translate exactly what it means and what your options are — free, confidential, and no pressure to sign anything.
Resolution program terms
These are the actual ways to fix a tax debt. Which one fits depends entirely on your numbers.
- Installment Agreement (IA) — a monthly payment plan. "Streamlined" agreements for balances under about $50,000 can usually be set up without detailed financial disclosure (see the IRS payment plans page).
- Partial-Pay Installment Agreement (PPIA) — monthly payments that won't cover the full debt before the CSED expires, so part of the balance is never collected.
- Offer in Compromise (OIC) — settling for less than the full balance when paying in full would create hardship. The IRS does the math; the marketing doesn't. Learn how it really works in our guide to how an Offer in Compromise actually works.
- Currently Not Collectible (CNC) — a hardship status that pauses collection when you can't pay anything without falling behind on basics.
- Penalty Abatement — removing penalties (not the tax) when you qualify for first-time or reasonable-cause relief.
- Innocent Spouse Relief — relief from tax caused by a spouse or ex-spouse's errors on a joint return.
- Fresh Start — not a single program but a set of IRS rule changes that made payment plans and Offers easier to get.
Forms and documents you'll hear about
- Form 9465 — the request for an installment agreement.
- Form 433-A / 433-F — financial disclosure forms (a "Collection Information Statement") showing your income, expenses, and assets.
- Form 656 — the Offer in Compromise application.
- Form 843 — used to request abatement of certain penalties.
- Form 8857 — the request for innocent spouse relief.
- Form 12153 — the request for a Collection Due Process hearing.
- Account transcript — the IRS's official record of your account, with codes for every action. You can pull yours free through your IRS online account.
People and watchdog terms
- Enrolled Agent (EA) — a tax professional licensed by the IRS to represent taxpayers nationwide.
- CPA — a Certified Public Accountant, licensed by a state.
- Tax Attorney — a lawyer who handles tax matters, including court and the most serious cases.
- Power of Attorney (Form 2848) — the form that lets a professional speak to the IRS on your behalf.
- Taxpayer Advocate Service (TAS) — an independent office inside the IRS that helps when normal channels fail or you face hardship. Reach them through the Taxpayer Advocate Service.
How to use this glossary, step by step
- Find the code on your notice — the top or bottom corner has a letter-number code like CP14 or LT11. Match it to the notice terms above.
- Pull your account transcript from your IRS online account so you can see the real balance and the dates.
- Find your CSED — knowing how much of the 10-year clock is left often changes the best strategy.
- Match a program to your numbers — a payment plan, hardship status, penalty relief, or an Offer, depending on what you can actually afford.
- Get a second opinion before paying for help — anyone guaranteeing a settlement before seeing your finances is selling you something.
Tax resolution glossary FAQs
What is the difference between a lien and a levy?
A lien is a legal claim against your property that protects the government's interest in your debt — it doesn't take anything, but it can affect your ability to sell or borrow. A levy is the actual seizure of money or property, like a bank account or wages. A lien is the warning shot; a levy is the taking.
What does CSED mean?
CSED stands for Collection Statute Expiration Date. The IRS generally has 10 years from the date a tax is assessed to collect it. After the CSED passes, the IRS can no longer legally collect that debt. Certain actions, like filing an Offer in Compromise or bankruptcy, can pause and extend that 10-year clock.
What is an Offer in Compromise?
An Offer in Compromise (OIC) is an IRS program that lets some taxpayers settle a tax debt for less than the full amount owed. It is real, but it is not for everyone — the IRS calculates what it believes it could collect from your income and assets, and you only qualify when paying in full would create genuine hardship. Anyone promising to settle your debt for pennies on the dollar before reviewing your finances is selling you something.
What does Currently Not Collectible mean?
Currently Not Collectible (CNC) is a status the IRS grants when paying anything toward your tax debt would leave you unable to cover basic living expenses. While you're in CNC, the IRS pauses garnishments and levies. The debt doesn't go away and interest keeps adding up, but active collection stops until your finances improve.
What is the difference between failure-to-file and failure-to-pay penalties?
The failure-to-file penalty applies when you don't file your return on time and is much steeper — 5% of the unpaid tax per month, up to 25%. The failure-to-pay penalty applies when you file but don't pay and is 0.5% per month, also capped at 25%. This is why you should always file on time even if you can't pay.
This guide is general information, not tax or legal advice for your specific situation. Eligibility for IRS programs depends on individual facts and circumstances; no outcome is guaranteed.