A tax notice is a formal letter from a taxing authority, most often the IRS, telling you that something on your tax account needs attention. It might say you owe a balance, that a number on your return didn’t match what a third party reported, that your refund was reduced, or that the agency needs documentation to verify something you claimed. Every notice carries a deadline, and the deadline is the part that matters most. Miss it and the IRS can assess the proposed amount automatically, then start adding penalties, interest, and eventually collection actions on top.
The good news is that a notice is not an accusation and not the end of the conversation. It is the start of one, and how you handle the first few weeks usually decides whether the problem closes quietly or grows.
Why the IRS Sends Notices
Notices are not random. The IRS sends one when its records don’t match yours, when money is owed, or when it needs more information. A CP14 is the standard balance-due letter for individuals and typically asks for payment within 21 days. A CP2000 comes out of the Automated Underreporter program, which compares the income on your return against W-2s, 1099s, and similar forms filed by employers, banks, and brokerages; if the numbers don’t line up, the IRS proposes a higher tax bill and gives you 30 days to respond, or 60 if you live outside the United States.1Internal Revenue Service. Topic No. 652, Notice of Underreported Income – CP2000
Other common triggers include math or clerical corrections the IRS made itself (you generally don’t need to amend, but check the fix), a smaller refund because the Treasury Offset Program redirected part of it toward past-due child support, federal student loans, state income tax debts, or certain unemployment debts,2Internal Revenue Service. Reduced Refund a correspondence examination asking for records that back up a deduction or credit, or an identity theft alert. Confirmed identity theft victims receive a CP01A each year with a six-digit Identity Protection PIN to use on future returns.3Internal Revenue Service. Get an Identity Protection PIN
Is the Notice Real?
Tax scams have gotten sophisticated, so verify before you act. The IRS initiates contact by postal mail. It does not open a case by email, text message, or social media, and it will not ask for personal or financial information through those channels. Every legitimate letter shows a notice or letter number, like CP14 or LTR 525, in the upper corner.
There is one exception worth knowing about. The IRS assigns certain overdue accounts to private collection agencies, and those agencies may call. Before that happens, the IRS first mails you a CP40 with a Taxpayer Authentication Number, and the collector then sends its own letter carrying the same number. If someone claims to be collecting for the IRS but you never received a CP40, treat it as a red flag.4Internal Revenue Service. Private Debt Collection
The fastest confirmation is your IRS Online Account, which shows digital copies of notices the agency has sent you.5Internal Revenue Service. Online Account for Individuals A tax transcript, available instantly online or by mail in 5 to 10 days, will show whether the balance or adjustment described in the letter actually appears on your account.6Internal Revenue Service. Get Your Tax Records and Transcripts If anything still feels off, call the IRS using the number on the notice or the main number on irs.gov, never a number provided in a suspicious letter.
What to Do First
Read the whole notice before you do anything. Three things need to come out of that reading: the specific tax year, the exact dollar amount at issue, and the response deadline. Write them down.
Then pull the records. If the notice challenges a deduction, gather the receipts and documents that support it. If it flags unreported income, dig out the W-2s, 1099s, and brokerage statements from that year and compare them line by line against what you filed. Missing income notices very often trace to a form the taxpayer forgot about, such as a 1099-INT from a rarely used savings account.
Once you have looked at the numbers, decide: is the notice right or wrong? If it’s right and you owe, paying quickly stops penalties and interest from growing. If it’s wrong, your documentation is the foundation of your response.
How to Respond
By Mail
Send your reply by certified mail with return receipt requested. That receipt is your proof of timely submission if the IRS ever claims nothing arrived. Include the notice number, the tax year, and your Social Security number or EIN. State plainly why you disagree, and attach copies (never originals) of the supporting documents. A short cover page listing each enclosure helps the examiner and helps you.
Online
The IRS Document Upload Tool accepts scanned documents, photos, and PDFs in response to many notice types. You’ll need either the access code printed on your notice or the notice number itself, along with your name and taxpayer identification number. Pick the correct notice type from the dropdown; the wrong selection can delay processing.7Internal Revenue Service. IRS Document Upload Tool The tool does not accept tax returns.
Paying
If you agree with the amount, IRS Direct Pay transfers funds from a bank account for free with no registration.8Internal Revenue Service. Direct Pay with Bank Account You can select the specific notice number as the reason for payment so the IRS applies it correctly.9Internal Revenue Service. Types of Payments Available to Individuals Through Direct Pay Checks and money orders work too; include the payment voucher that came with the notice. Cards are accepted but carry a processor fee.
The 90-Day Letter
One notice deserves special attention. A Statutory Notice of Deficiency, sometimes called a 90-day letter and often numbered CP3219N, gives you exactly 90 days from the date on the notice (150 days if you’re abroad) to file a petition with the U.S. Tax Court. Filing a late return does not extend the window. If the amount at issue is $50,000 or less per year, the Tax Court offers simplified small-case procedures.10Internal Revenue Service. Understanding Your CP3219N Notice Miss the 90 days and you lose the right to challenge the assessment in Tax Court before paying. That mistake is expensive and essentially irreversible.
Appeals
If you disagree with the IRS’s final determination after your first response, you can ask for review by the IRS Independent Office of Appeals. It’s internal but independent, designed to resolve disputes without litigation, and often worth trying before court.11Internal Revenue Service. Appeals
What Delay Costs
Two charges run at the same time on an overdue account. The failure-to-file penalty is 5% of the unpaid tax for each month or partial month a return is late, capped at 25%. The failure-to-pay penalty is 0.5% per month on the unpaid balance, also capped at 25%.12Office of the Law Revision Counsel. 26 USC 6651 – Failure to File Tax Return or to Pay Tax When both apply in the same month, the failure-to-file penalty is reduced by the failure-to-pay amount, so the combined rate is 5% per month for the first five months.13Internal Revenue Service. Failure to File Penalty The practical rule: if you can’t pay, file anyway. Filing on time eliminates the larger penalty entirely.
Interest is separate. It runs from the original due date until the balance is paid, at a rate the IRS sets quarterly. For the first quarter of 2026 the individual underpayment rate is 7% per year, compounded daily.14Internal Revenue Service. Interest Rates Remain the Same for the First Quarter of 2026 On a $10,000 balance, that is roughly $700 a year in interest alone, before penalties.
Penalties can sometimes be reduced or removed through first-time abatement (if you have a clean penalty record for the prior three years and are current on filings) or reasonable cause relief for circumstances like serious illness, death in the immediate family, or a natural disaster. Not knowing the rules, blaming a preparer, or lacking funds generally do not qualify. Interest on the underlying tax keeps accruing even when penalties come off.15Internal Revenue Service. Penalty Relief for Reasonable Cause
If You Can’t Pay in Full
Owing more than you can pay right now is not the same as having no options. Ignoring the bill is the worst move because it triggers the collection escalation described below. The alternatives keep the IRS at the table.
Installment agreements spread the balance across monthly payments. You can apply online, by phone, or by mail; online carries lower setup fees, and short-term plans of 120 days or less have no setup fee at all. Interest and the reduced failure-to-pay penalty keep accruing during the plan, but active collection stops.
An offer in compromise settles the debt for less than the full amount when the IRS agrees you can’t pay it all. Eligibility requires filed returns, current estimated payments, no open bankruptcy, and (for employers) current payroll deposits. The application fee is $205, waived for low-income applicants, and a proposed payment must accompany the application.16Internal Revenue Service. Offer in Compromise Acceptance rates are low, so this fits when the math genuinely shows inability to pay.
Currently not collectible status is a pause. If paying anything would leave you unable to cover basic living expenses, the IRS can suspend active collection after you document your finances, typically on Form 433-A. Penalties and interest keep accumulating, but levies are held off.17Internal Revenue Service. 5.16.1 Currently Not Collectible
The Taxpayer Advocate Service can step in if you’re facing economic hardship, significant costs, or a case that has gone more than 30 days without resolution through normal channels. TAS is independent within the IRS, and its help is free.18Internal Revenue Service. Who May Use the Taxpayer Advocate Service?
If You Do Nothing
Ignoring a notice triggers an escalating collection process, and each step gives the IRS more reach into your finances. It begins with a demand for payment in full, penalties and interest included. If the balance stays unpaid, the IRS can file a Notice of Federal Tax Lien, a public record that attaches to your property (including property you acquire later), alerts creditors, damages your credit, and complicates any sale or loan.19Internal Revenue Service. Topic No. 201, The Collection Process
From there the IRS can issue a levy, which is an actual seizure. Levies can reach wages, bank accounts, Social Security benefits, retirement income, refunds (federal and state), and physical property such as vehicles and real estate.19Internal Revenue Service. Topic No. 201, The Collection Process By the time a case reaches that point, you have received multiple notices and had several chances to respond. The IRS does not skip steps, but it also does not stop.
Your Rights and When to Get Help
Every dealing with the IRS is governed by the Taxpayer Bill of Rights, which includes the right to be informed and receive clear explanations, the right to challenge the IRS’s position and be heard, the right to appeal in an independent forum, and the right to finality on how long the IRS has to audit a year or collect a debt.20Internal Revenue Service. Taxpayer Bill of Rights
You also have the right to be represented. Once a notice moves past a simple balance-due situation, especially into an examination or a proposed deficiency, professional help can change the outcome. Attorneys, CPAs, and enrolled agents can represent you before the IRS using Form 2848, Power of Attorney. An unenrolled preparer who signed your return has limited authority on matters tied to that return.21Internal Revenue Service. Form 2848, Power of Attorney and Declaration of Representative If cost is the barrier, Low Income Taxpayer Clinics provide free or low-cost help, and the Taxpayer Advocate Service can point you to one.20Internal Revenue Service. Taxpayer Bill of Rights
A tax notice, in the end, is a document with a clock on it. Read it, verify it, gather your records, and respond by the date printed on the page. The system is designed to work with you as long as you engage with it.