IRS notice guide

Your business received an IRS notice — what to do right now

Written by CompDefend. Founded by Umair Nazir, EA — Enrolled Agent, federally licensed to practice before the IRS. Last updated 2026-08-27.

The first thing to do when your business receives an IRS notice is not to ignore it, and the second is to find out what it actually is before doing anything else. Read the document for four things: the notice or letter number, the tax form and tax period, the amount or the action the IRS is requesting, and the response or payment deadline printed on it. The IRS states that you should review the notice carefully, keep it for your records, and act by the due date if a response is requested. Most notices do not require a panic — but a notice with a printed deadline that goes unanswered is how small problems become larger ones.

Do not ignore the communication

Ignoring an IRS notice is the one action that reliably makes the situation worse. An unanswered balance-due notice keeps accruing penalty and interest, and the reminder sequence can move toward a federal tax lien or levy. An unanswered information request in an examination can lead to the IRS determining the facts from what it has, or to a summons. Acting by the printed deadline is what the IRS asks for, and it is what preserves your options — including your appeal rights if you disagree.

Step 1: determine which notice or letter you have

Find the CP or LTR number in the right corner of the letter. That number tells you which notice you are holding, and the IRS publishes an explanation page for most of them. The full guide to reading an IRS notice walks through every part of the document; the business tax library lists the specific notice pages by situation, so you can find the one that matches the document in your hand.

Different notices are different kinds of events. A CP161 is a balance-due bill. A CP259 says the IRS expected a return it never received. A Letter 566 is part of a correspondence examination. A CP504B is a final warning before levy. Each one has its own meaning, its own deadline, and its own correct response — which is why identifying the number is the first step rather than a detail.

Step 2: verify it through official channels

Search the notice number on irs.gov. If the notice does not appear in the search, or if it looks suspicious, the IRS states that you should call 800-829-1040 and follow the representative’s instructions. Genuine IRS contact begins with a letter; the IRS does not demand payment by gift card, wire transfer, or cryptocurrency, and it does not threaten arrest over the phone.

Use contact information you found on irs.gov, not a number or address that arrived in an email or a text. If a message claims to be from the IRS and pressures you for immediate payment, treat it as a likely scam and report it rather than paying.

Step 3: note the notice number and the notice date

Write down both the notice number and the notice date. The number is the key to the IRS’s own explanation, and the date is what response windows are often counted from. A notice that says "contact us within 10 days of the date of this notice" runs from the printed date, not from the day you opened the envelope.

Step 4: identify the tax form and tax period

The notice names a form — 941, 940, 1120-S, 1065, 1120 — and a period: a quarter, a calendar year, or a date range. Record both. They tell you which module of the IRS account the notice belongs to and, therefore, which records you will need. If the notice does not state them, the business tax transcript for the EIN shows which modules exist.

Step 5: locate the printed deadline

Find the words "by", "due date", "respond by", or "pay by" and the date after them. The date printed on your notice controls. There is no universal IRS deadline that applies to every notice, and no two notices necessarily follow the same path, so do not rely on a number you saw somewhere else — read the date on the document in front of you.

Some notices carry two dates, and some ask you to count days from the notice date. Read the sentence next to each date. If you cannot tell which date applies, the safest action is to meet the earliest one while you work out the rest.

Step 6: determine what the IRS wants

Read the words around the dollar figure and the instruction block. The IRS is usually asking one of a small number of things: payment of a balance due, a response to a proposed adjustment, information or records, verification of identity, or — sometimes — nothing at all beyond keeping the notice for your records. A "for your records" notice still belongs in your file, but it does not demand a reply.

Step 7: decide — agree, disagree, or cannot pay

Once you know what the IRS wants, the decision is a three-way fork. If the business agrees with the notice, take the requested action by the deadline — pay the balance, or return the information. If it disagrees, respond by the deadline with the documents and explanation the notice asks for; the IRS guidance states that replying by the due date is what preserves your appeal rights. If the business cannot pay in full, pay what it can and contact the IRS by the deadline to arrange a payment path — the IRS states that even if you cannot pay the full amount, paying by the due date can reduce interest and penalty charges.

These three paths are not interchangeable. Paying a proposed amount you disagree with can look like agreement; disputing without the supporting documents can fail for lack of evidence; and ignoring a balance you cannot pay converts a payment problem into a collection problem. The notice’s own instructions name the path it expects.

Gather the records tied to the specific issue

Pull only the records the specific issue calls for. A balance-due notice needs payment history and the return; an information request in an examination needs the documents it lists; a TIN-mismatch notice needs the W-9s. Over-producing unrelated records can slow a dispute and, in an examination, hand an examiner material they did not ask for.

Preserve copies and proof of delivery

Keep a copy of the notice, a copy of everything you send, and proof of delivery or submission. For mail, that means a service that gives you a tracking or delivery record; for fax or an IRS portal, keep the confirmation. If the IRS later says it never received your response, the proof of delivery is what moves the dispute from "your word against ours" to a documented timeline.

Store the notice with the return and the records for that period. The paper trail — what the IRS said, when you answered, and how — is exactly what a later penalty dispute or an examination needs, and it cannot be reconstructed from memory months later.

When professional involvement becomes appropriate

Many notices can be handled by the business owner directly when the amount is modest, the figures match the records, and the issue is a single period. A qualified tax professional — a CPA or enrolled agent, or a tax attorney where personal exposure is possible — becomes appropriate when the notice involves an examination or information request, a lien or levy step, a balance spanning several periods, withheld payroll taxes the business cannot cover, or any risk that an owner, officer, or responsible person could face personal liability.

There is an important distinction in how a professional can help. A professional who will speak or act for the business before the IRS needs a Form 2848 power of attorney. Form 8821, a tax information authorization, only lets a person or company see tax information — it is not representation. CompDefend works under Form 8821 to read supported account information and does not represent anyone before the IRS; the distinction is explained in the Form 8821 guide.

Not every notice is an audit or a collection action

A notice is mail, not a verdict. The large majority of IRS notices are routine account communications: a balance-due reminder, a penalty computation, a return-correction explanation, a request for a missing form. A notice is not automatically an audit, and it is not automatically a collection action. The IRS frames examinations as conducted by mail or in person, and a correspondence examination is a specific kind of event with its own letter and process — it is not what a balance-due notice is doing. Reading the notice number before reacting keeps you from treating a routine reminder as an audit or, just as costly, treating an intent-to-levy notice as a routine reminder.

Where to go from here

If the notice is still in front of you and you are not sure which part means what, the full guide to reading an IRS notice explains every section of the document — number, addressee, form, period, amount, deadline, contact, appeal rights, enclosures, and verification — with an anatomy diagram. The specific notice pages explain individual CP and letter numbers, and the transcript guide shows what the account behind the notice contains.

Once the immediate question is answered — which notice it is, what it is asking, and by when — the broader question is what the notice says about the business’s overall posture. The Federal Tax Defensibility Index measures how well the applicable federal tax posture appears supported, and the free business tax check returns the index with the weak areas named. That is the step after the urgent response, not before it.