Search the notices
Filtering runs in your browser. A clock of “Date on the notice” means the IRS page gives no fixed period; use the response or payment date printed on the client's copy.
| Notice | What it means | Clock | Source |
|---|---|---|---|
| CP11 | The IRS corrected mistakes on the return and the amount owed changed. | Date on the notice | IRS CP11 page |
| CP12 | The IRS corrected mistakes on the return; a refund is now due or the refund amount changed. | Date on the notice | IRS CP12 page |
| CP14 | Balance due on unpaid taxes (first bill). | Date on the notice | IRS CP14 page |
| CP22A | The IRS made changes to the return, and the taxpayer owes because of them. | Date on the notice | IRS CP22A page |
| CP59 | The IRS has no record that a prior year personal return was filed. | Date on the notice | IRS CP59 page |
| CP71 | Annual reminder of an unpaid balance; also explains passport denial or revocation for seriously delinquent debt. | Pay or contact the IRS | IRS CP71 page |
| CP90 | Intent to levy certain assets, with the right to a Collection Due Process hearing. | 30 days from the notice to request CDP (Form 12153) | IRS Appeals letters page |
| CP161 | Business balance due on a return with no math error. | Contact within 10 days if wrong; pay by the date shown | IRS CP161 page; IRM 3.14.2.6.9 |
| CP162 series | Partnership or S corporation penalty: CP162 (failure to e-file), CP162A (late return), CP162B (missing information). | Pay by the date shown; abatement by request | IRM 3.14.2.6.10 |
| CP215 | A civil penalty was assessed on a civil penalty module. | 10 days to send a written explanation without paying first | IRS CP215 page; IRM 21.3.8.10.2.8 |
| CP501 | Reminder of a balance due when no payment or response to the earlier notice arrived. | Date on the notice | IRS CP501 page |
| CP503 | Second reminder: still no response and an unpaid balance. | Date on the notice | IRS CP503 page |
| CP504 | Notice of intent to levy under IRC 6331(d) (state refunds and certain property). | Pay immediately or contact the IRS | IRS CP504 page |
| CP2000 | Third-party income or payment information does not match the return; proposed changes. | Reply by the date listed | IRS CP2000 page |
| CP2057 | Soft notice: income may be missing; amend if correct. No case and no proposed tax. | No reply date | IRS CP2057 page; IRM Exhibit 4.19.2-1 |
| CP2501 | Third-party information does not match the return; the IRS asks for an explanation. | Reply by the date listed | IRS CP2501 page |
| CP3219A | Automated Underreporter statutory notice of deficiency. | 90 days to petition the Tax Court (150 abroad) | IRM 4.19.3.2.1.1 |
| LT11 / Letter 1058 | Final notice of intent to levy, with the right to a CDP hearing. | 30 days from the letter to request CDP | IRS LT11 page; IRS Appeals letters page |
| LT16 | The IRS is trying to collect unpaid taxes and/or is missing returns. | Contact the IRS promptly | IRS LT16 page |
| Letter 525 | Correspondence exam report (Form 4549) with options to agree or appeal. | 30 days to respond or protest | IRS Appeals letters page |
| Letter 566 | Correspondence exam initial contact asking for documents on listed items. | Date on the letter; first 30-day extension is automatic | IRM 4.19.13.8; IRM 4.19.13.11.7 |
| Letter 950 | Field exam 30-day letter with the revenue agent's unagreed report. | 30 days to protest | IRM 4.10.8.12.1 |
| Letter 1153 | Proposed trust fund recovery penalty against a responsible person. | 60 days to protest (75 abroad) | IRC 6672(b); IRM 8.25.1.4 |
| Letter 2205 | Field exam initial contact asking the taxpayer to call and schedule. | 14 calendar days to call | IRM 4.10.2.8.1.2 |
| Letter 226-J | Proposed employer shared responsibility payment (IRC 4980H). | Response date on the letter, generally 30 days | IRS ESRP Q&A |
| Letter 3172 | Notice of federal tax lien filing and the right to a CDP hearing. | Date on the letter (30-day period after 5 business days from filing) | IRC 6320; IRM 5.12.6.3 |
| Letter 3219 | Correspondence exam statutory notice of deficiency. | 90 days to petition the Tax Court (150 abroad) | IRC 6213(a); IRM 4.19.13.13 |
| Letter 5071C | Identity verification needed before the return is processed. | No date on the IRS page; return held until verified | IRS CP5071 series page |
| CP01A | Annual notice with a new identity protection PIN. | Use the IP PIN on the next return | IRS CP01A page |
| CP05 | The IRS needs more time to verify income, withholding, credits or business income. | Allow up to 60 days before contacting the IRS | IRS CP05 page |
| CP21A | The IRS made the requested changes to the return and the taxpayer owes. | Date on the notice | IRS CP21A page |
| CP75 | Correspondence exam of the Earned Income Credit; refund portions held pending documents. | Date on the notice | IRS CP75 page; IRM 4.19.20.2.1 |
| CP92 | The IRS levied a state tax refund; post-levy CDP right. | 30 days to request CDP | IRS Appeals letters page |
| CP134B | Federal tax deposits credited do not match the deposits reported on the return. | Pay by the date on the notice | IRS CP134B page |
| CP220J | Notice and demand for an assessed employer shared responsibility payment. | Pay; subject to lien and levy | IRS CP220J page |
| CP242 | Notice of levy on a state tax refund; post-levy CDP right. | 30 days to request CDP | IRS Appeals letters page |
| CP297 | Final notice of intent to levy with the right to a CDP hearing. | 30 days to request CDP | IRS Appeals letters page |
| CP297A | The IRS levied assets; CDP right after the levy. | Date on the notice | IRS CP297A page |
| CP504B | Business notice of intent to levy under IRC 6331(d); a lien may also be filed. | Pay immediately or contact the IRS | IRS CP504B page; IRM 21.3.8.10.2.4 |
| CP523 | Intent to terminate an installment agreement in default and to levy. | Appeal by following the notice; termination in 30 days | IRS Appeals letters page |
| CP2005 | The IRS accepted the information sent and closed its review with no change. | None | IRS CP2005 page |
| CP3500 | The IRS received the taxpayer's or representative's response and needs more time. | None | IRS CP3500 page |
| Letter 11 | Final notice of intent to levy with the right to a CDP hearing. | 30 days to request CDP | IRS Appeals letters page |
| Letter 227 series | Acknowledges an employer's response to Letter 226-J and states next steps. | Date on the letter | IRS Letter 227 page |
| Letter 531 | Notice of deficiency (field and office exams). | 90 days to petition the Tax Court | IRS Appeals letters page |
| Letter 555 | Exam reply after the 90-day letter: report unchanged; the petition date does not move. | Petition deadline unchanged | IRM 4.19.13.11.2 |
| Letter 692 | Request for consideration of additional findings (revised report). | 15 days to respond or protest | IRS Appeals letters page |
| Letter 915 | Office exam report transmittal (30-day letter). | 30 days to protest | IRS Appeals letters page |
| Letter 1085 | 30-day letter proposing an IRC 6020(b) return the IRS prepared for a business. | Date on the letter | IRS Appeals letters page |
| Letter 1153-W | Rescinds a proposed trust fund recovery penalty for listed periods. | None | IRM 5.7.4.7 |
| Letter 2295 | Follow-up to an unanswered field exam contact: liability may be changed or a summons issued. | Respond promptly | IRM 4.10.2.8.3 |
| Letter 3391 | 30-day nonfiler letter with a proposed computation. | 30 days to protest | IRS Appeals letters page |
| Letter 4883C | Identity verification letter that requires a phone call. | Call the number on the letter | IRM 25.25.6 |
| Letter 5040-J | Second notice when Letter 226-J got no response. | 15 days | IRM 25.21.4.14.1 |
| Letter 5447C | Identity verification letter for a foreign address. | Per the letter | IRM 25.25.6 |
Reading a notice number
CP notices (Computer Paragraph notices, as IRM 4.19.13.2.3 calls them) are generated from account conditions: a balance due, a math correction, an information return mismatch. Suffix letters often mark variants: the CP162A and CP162B are separate penalty notices (IRM 3.14.2.6.10), the CP504B is the business version of the CP504, and a Spanish version may carry a different number (the CP161 is the CP861 in Spanish).
Letters are prepared by IRS staff or generated by a program (IRM 4.19.13.2.3 notes campus letters can be prepared by clerical staff or tax examiners), often with a suffix that marks a variant: Letter 566-S, 566-B and 566-T are different initial contact letters; Letter 950-F and 950-Z are different 30-day letters. The base number usually tells you the stage (initial contact, report, notice of deficiency), and the suffix tells you the program or format.
LT11 and Letter 1058 are different documents that both carry levy CDP rights, which is why they share a page here.
When the number is not on this list, the account transcript for the period shows the assessments and transactions behind most notices. See reading an account transcript and the transcript code decoder.
Which clocks are statutory
| Kind of clock | Examples | Can the IRS extend it? |
|---|---|---|
| Tax Court petition after a notice of deficiency | CP3219A, Letter 3219, Letter 531 | No. IRC 6213(a); IRM 4.19.3.2.1.1 says employees can't extend it. |
| CDP hearing request | Letter 3172, LT11 / Letter 1058, CP90 | No. A late request can be an equivalent hearing within one year. |
| TFRP protest | Letter 1153 | Set by IRC 6672(b); a timely mailed protest is timely. |
| Administrative response dates | Letter 525, Letter 950, CP2000, Letter 566 | Often, on request. Missing them moves the case to the next step. |
The order of operations when a notice arrives is on responding to an IRS notice as a representative. For payer notices about information returns (CP2100 and CP2100A backup withholding notices, Notice 972CG penalty proposals), see the CP2100 guide and the 972CG guide on TIN Compliance.
Questions practitioners ask
The client's notice is not listed. Where do I look?
Start with the IRS's Understanding your IRS notice or letter search, then the account transcript for the period, which shows the transaction behind most notices.
Is the response date on the notice the legal deadline?
Only for statutory notices such as notices of deficiency and CDP notices. For most other notices it is an administrative date, and missing it moves the case forward rather than ending rights.
What is the difference between a CP2000 and a CP2057?
A CP2000 proposes specific changes and leads to a notice of deficiency if unresolved. A CP2057 is a soft notice with no case and no proposed tax.
Do Spanish notices have different numbers?
Some do. For example, IRM 3.14.2.6.9 identifies the CP861 as the Spanish version of the CP161.
Which notices carry Tax Court rights?
Notices of deficiency (CP3219A, Letter 3219, Letter 531) and CDP determinations after a timely hearing request. Most balance due and penalty notices do not.