It’s a letter. It is not a verdict.
Most of them are a computer noticing a mismatch.
A few of them have a deadline that matters.
Open it, find the date, and call.
Welcome. We’re glad to serve you.
The IRS sends tens of millions of letters a year. Most are not audits. They are a computer comparing what a bank or employer reported to what your return said, or a notice that a balance exists, or a request to verify your identity. Each one has a number in the corner, a date, and a deadline, and the deadline is the only thing you need to find before you call us.
Below is what the common letters mean, how the penalties work and how they stack, the one-call fix called first-time abatement that removes penalties for people with a clean record, what to do when you can’t pay, and the clocks that run in both directions: how long the IRS has to come after you, and how long you have to get money back.
| Notice | What it means | Deadline |
|---|---|---|
| CP2000 | Income reported to the IRS (a 1099, a W-2, a brokerage sale) doesn’t match your return. It proposes a change and a tax. It is not an audit and not a bill yet. | 30 days to agree or disagree |
| CP11 / CP12 | A math or clerical error was corrected; you owe more (CP11) or get a different refund (CP12). | 60 days to dispute, or the change stands |
| CP14 | The first bill: tax shown on your return that wasn’t paid, with penalty and interest. | 21 days before more interest and the next notice |
| CP501, CP503 | Reminders of the balance. Nothing new, more interest. | Pay or arrange before the next one |
| CP504 | Notice of intent to levy your state refund; a warning that enforced collection is next. | 30 days |
| LT11 / Letter 1058 | Final notice of intent to levy and your right to a hearing. After this the IRS can take wages and bank accounts. | 30 days to request a collection due process hearing, which stops the levy |
| CP49 | Your refund was applied to a balance from another year. | None; informational |
| 5071C / 4883C | Identity verification. A return was filed in your name and the IRS wants to confirm it was you. | Respond promptly; the refund is held until you do |
| Letter 525 / 2205 | An actual examination (audit), by mail or in person. | As stated; usually 30 days |
| CP90 / CP297 | Final notice before levy on Social Security benefits or federal payments. | 30 days |
The ones in bold are the ones that cannot wait. An LT11 ignored for 31 days is a levy on your paycheck. Everything else is correctable, usually by letter, without drama.
↑ Back to topA CP2000 is the most common letter we see, and about half the time the IRS is wrong or half right: the sale on the 1099-B had basis the broker didn’t report, the 1099-R was a rollover, the income was reported on a different line. The response is a signed form with a short explanation and the document that proves it. Don’t sign the agreement page if you disagree with any of it, and don’t pay a proposed amount you dispute; paying is agreeing. If the IRS is right, sign, pay, and ask about the penalty below.
For every letter: respond in writing, by the date, keep a copy, and send it certified. Phone calls to the IRS can take two hours and leave no record. If the deadline is close, a one-line letter asking for 30 more days is routinely granted and stops nothing bad from happening. If the letter asks you to call a number or click a link, confirm the number against irs.gov first; the IRS does not initiate contact by email or text, and a “notice” demanding gift cards is a crime, not a tax.
↑ Back to top| Penalty | Rate | Cap |
|---|---|---|
| Failure to file (return late, tax owed) | 5% of the unpaid tax per month or part of a month | 25%; minimum $525 if over 60 days late (verify 2026 minimum) |
| Failure to pay (tax not paid by April 15) | 0.5% per month; 0.25% while an installment agreement is in place; 1% after a levy notice | 25% |
| Both in the same month | The file penalty drops to 4.5% so the pair totals 5% | 47.5% combined over time |
| Accuracy-related (substantial understatement or negligence) | 20% of the underpayment | 40% for gross valuation misstatements |
| Estimated tax (underpaid during the year) | Interest at the federal rate, by quarter | See our W-4 page for the safe harbors |
| Fraud | 75% | Rare; requires intent |
The failure-to-file penalty is ten times the failure-to-pay penalty. That is the whole lesson of this section: file on time even if you can’t pay. A $10,000 balance filed on time and paid six months late costs $300 in penalty. The same balance on a return filed six months late costs $2,500 plus the $300. An extension moves the filing deadline to October 15 but not the payment deadline, so the 0.5% still runs from April on whatever wasn’t paid.
I didn’t file because I couldn’t pay. The not-filing cost more than the not-paying. The system is designed by people who assume you’ll read the fine print on the way down.
↑ Back to topInterest runs on unpaid tax from the original due date, and on penalties from the date they’re assessed, compounded daily. The rate for the last quarter of 2026 is 7%. Interest is almost never abated; the law allows it only when the IRS itself caused an unreasonable delay. When a penalty is abated, the interest that accrued on that penalty goes with it, which is a reason to pursue abatement even on small balances.
↑ Back to topIf you have no penalties in the prior three years, all your returns are filed, and your current balance is paid or on a payment plan, the IRS will remove the failure-to-file and failure-to-pay penalties (and the failure-to-deposit penalty for employers) for one year, on request, no explanation needed. It is a policy, not a law, and it is granted by phone or in a short letter. It does not cover the accuracy penalty or the estimated-tax penalty.
Two things people get wrong. It is available once per clean three-year window, not once in a lifetime; a taxpayer with a penalty in 2019 and nothing since can use it for 2026. And the IRS will not offer it; you ask. We ask on every balance-due notice that comes through the office, because the answer is yes more often than not and the amounts are real: $2,500 of failure-to-file penalty on a late return is a phone call.
↑ Back to topIf first-time abatement isn’t available, penalties can still be removed for reasonable cause: you exercised ordinary care and still couldn’t comply. Serious illness or death in the immediate family, a fire or disaster that destroyed records, an inability to get records that you tried to get, and in some cases reliance on wrong advice from a professional. Not reasonable cause: not having the money, forgetting, being busy, not knowing the rule, or relying on a preparer to file (the duty to file is yours). The request is a letter with dates and documents, and the standard is whether a careful person in your situation would have been late too. We write these when the facts support them and tell you when they don’t.
↑ Back to topNone of these stops a levy once an LT11 has run out. The 30-day hearing request does. Then the plan is negotiated inside the hearing.
↑ Back to topThe Colorado Department of Revenue runs its own notices, usually a few months after the IRS makes a change, because it receives the federal adjustment and recomputes. If a CP2000 changes your federal return, Colorado expects an amended Colorado return (DR 0104X) within 30 days of the final federal determination, and will bill you if it doesn’t get one. Colorado’s late-filing penalty is the greater of $5 or 5% of the unpaid tax plus 0.5% per month, to a maximum of 12% (verify), and its interest rate is set annually (verify 2026 rate). The Department will abate penalties for reasonable cause on a written request and offers payment plans through its online account; it has no formal first-time abatement policy, but a first request with a clean history is usually granted. Colorado also sends identity-verification letters of its own, and they hold refunds the same way.
↑ Back to topThe IRS was told the sale price and nothing else. If the broker didn’t report your cost, the whole sale looks like gain. Respond with the basis and the proof; the proposed tax usually drops to a fraction or to zero. Don’t sign the agreement page and don’t pay until it’s resolved.
If you had no penalties in the prior three years and your returns are filed, ask for first-time abatement. It is granted on request, by phone or letter, and the interest on the penalty is removed with it. We make the request as a matter of course.
No. File on time and pay what you can. The late-filing penalty is 5% a month; the late-payment penalty is 0.5%. Then set up an installment agreement online, which also cuts the payment penalty in half. Waiting to file is the most expensive choice available.
After 30 days the IRS can take money from your bank account and a share of each paycheck without further notice. Within the 30 days you can request a hearing, which stops the levy while a payment plan or other resolution is worked out. Call the day it arrives.
For the Tax Shop desk · forms, code sections, and the things that get missed
Bring the letter the day it arrives, not the week the deadline passes. Half of the notices we see are resolved with one page and a copy of a document the IRS didn’t have. Most of the penalties we see are removed with a phone call, if the record is clean, or a letter, if the reason is real. The remaining cases need a payment plan or a hearing, and both are better started early. We represent clients before the IRS and the Colorado Department of Revenue; a signed authorization lets us make the calls so you don’t have to.
Call 303-734-1040 or stop by the office in Lone Tree. We’ve been reading the footnotes for Douglas County and the Denver area since 1969.
Figures reflect the 2026 tax year as currently published and are rounded for readability. Items marked (verify) are to be confirmed against IRS or Colorado DOR sources before the figures freeze in December. Last updated October 15, 2026.