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IRS Notice Lookup

The IRS sends notices in a structured escalation sequence. Search below to find your notice, understand where it falls in that sequence, and learn exactly what to do next.

The IRS Collection Sequence

IRS collection follows a statutory path: balance due notices (CP14, CP501, CP503) → intent to levy (CP504) → final notice with CDP rights (LT11 / Letter 1058) → actual levy. Each step has specific response opportunities and deadlines. The single most important deadline: the 30-day CDP window from the LT11. Letting it pass eliminates your formal right to challenge the levy before it happens.

Showing 25 of 25 notices

CP11Math Error — Balance Due After Credits Applied

MediumBalance Due

What it means: The IRS recalculated your return and found a math error that resulted in a balance due. Credits you claimed were adjusted — often the Earned Income Credit, Child Tax Credit, or American Opportunity Credit. The notice shows the exact line-by-line changes and the resulting amount owed, along with any failure-to-pay penalties already accruing.

What to do: Review the IRS's changes against your original return line-by-line. If you agree, pay by the response date or set up a payment plan. If you disagree, respond in writing within 60 days with documentation — W-2s, 1099s, receipts — that supports your original figures. Do not simply pay without reviewing; many CP11 adjustments are disputable.

60 days to dispute; payment due date shown on noticeIRS.gov reference →

CP12Math Error — Overpayment After Correction

LowAdjustments

What it means: The IRS found a math error on your return, but the correction results in an overpayment — meaning you'll receive a larger refund than you originally calculated, or a refund you weren't expecting. The notice explains exactly what was changed and the adjusted refund amount. No penalty applies because you overpaid.

What to do: Review the changes. If you agree, no action is required — the IRS will issue the corrected refund automatically within 4–6 weeks. If you disagree with what the IRS changed, respond within 60 days with supporting documentation. Keep this notice for your records.

60 days to dispute if you disagree with the IRS's correctionIRS.gov reference →

CP14First Balance Due Notice

MediumBalance Due

What it means: The IRS calculated that you owe taxes for the year shown. This is the first formal notice in the IRS collection sequence and includes the balance owed, interest accrued through the notice date, and any failure-to-pay penalties already assessed (typically 0.5% per month). This is a statutory demand for payment — not yet enforcement — but it starts the clock on the escalation sequence that eventually leads to levies.

What to do: Do not ignore it. If you agree with the amount, pay by the due date shown or apply for an installment agreement immediately. If you disagree, contact TaxWave or call the IRS within 60 days to dispute the assessment. Every notice you ignore without action adds more interest and penalties — the balance compounds from this point forward.

21 days to pay before additional penalties accrue; 60 days to formally disputeIRS.gov reference →

CP21AChanges Made to Tax Return — Balance Due

MediumReturn Changes

What it means: The IRS made changes to your tax return based on information you provided — typically after an audit, in response to a prior notice, or following an amended return you filed — and there is now a balance due. The notice specifies which lines were changed, the original amounts, the corrected amounts, and the resulting balance including interest and any penalties assessed through the notice date.

What to do: Review the changes line-by-line against your records and the return you originally filed. If you agree, pay by the due date or request a payment plan. If the changes don't reflect what you submitted or agreed to, respond within 60 days with supporting documentation. Keep a copy of the original return and any amended return you filed for reference.

60 days to dispute; payment due date shown on noticeIRS.gov reference →

CP22AData Processing — Balance Due After Account Changes

MediumBalance Due

What it means: The IRS processed changes to your tax account — usually from an amended return you filed, a response to a prior IRS inquiry, or a data correction — and you now have a balance due. This is a standard billing notice following any account modification that creates a new liability. It may follow an amended return you filed that reduced a refund or created a new balance.

What to do: If you recognize and agreed to the changes that created this balance, pay by the due date or set up a payment plan. If the changes are unexpected and you did not initiate any account changes, contact the IRS immediately — unexpected account changes can indicate identity theft or an IRS processing error that needs to be corrected before any payment is made.

Payment due date shown on noticeIRS.gov reference →

CP23Estimated Tax Payment Mismatch — Balance Due

MediumEstimated Tax

What it means: The IRS's records show that the estimated tax payments (Form 1040-ES) you made during the year don't match what you reported on your tax return, resulting in a balance due. Common causes: payments posted to the wrong tax year (e.g., a Q4 payment posted to next year), discrepancies between the amount paid and what was entered on the return, or payments made under an incorrect SSN.

What to do: Compare your actual payment records — bank statements or IRS.gov payment history — against what the IRS is showing. If you know you made the payments and the IRS doesn't reflect them correctly, gather proof of payment and contact the IRS to have the payments applied to the correct tax year before paying any balance.

60 days to respond with corrected payment informationIRS.gov reference →

CP30Underpayment of Estimated Tax — Penalty Assessed

LowEstimated Tax

What it means: The IRS assessed an underpayment penalty under IRC §6654 because you didn't pay enough in estimated taxes throughout the year. The penalty is calculated on the quarterly shortfall between what you should have paid (based on your prior-year tax or 90% of current-year tax) and what you actually paid. The penalty rate is the federal short-term rate plus 3 percentage points — currently around 7–8% annualized.

What to do: If you believe you qualify for an underpayment exception — you met the prior-year safe harbor (100% or 110% for higher incomes), you had a casualty or disaster event, or you retired after age 62 — file Form 2210 with supporting calculations to request a waiver. Otherwise, pay the penalty amount. Consider adjusting your W-4 withholding or quarterly estimated payments going forward to avoid this penalty.

60 days to dispute or request exception waiver via Form 2210IRS.gov reference →

CP49Overpayment Applied to Past-Due Tax

LowAdjustments

What it means: You had a tax refund due for the current year, but the IRS applied all or part of it to a past-due balance on another tax year or account under IRC §6402. The notice shows the refund amount, how much was applied toward the prior debt, which year's debt it addressed, and any remaining refund being issued to you. This is an automatic IRS offset — no separate action triggered it.

What to do: Confirm that the prior-year balance cited in the notice is legitimate and correctly stated. If you dispute the underlying debt the IRS offset against — for example, if you believe the prior year was already resolved — contact TaxWave to challenge the underlying assessment. If the prior-year debt is genuinely paid or erroneous, the applied refund can be recovered.

60 days to dispute the underlying balance that was offset against your refundIRS.gov reference →

CP71CAnnual Reminder — Unpaid Balance Still Owed

MediumBalance Due

What it means: An annual account statement reminding you that you have an unpaid tax balance. Typically sent to taxpayers in low-priority collection status — Currently Not Collectible (CNC), OIC pending, or in a delayed collection queue. The balance shown reflects all accrued interest and penalties through the notice date, which may be dramatically higher than the original assessment if years have passed.

What to do: If you're already in an active resolution — installment agreement, OIC pending, or CNC status — this notice generally doesn't require immediate action. Verify with TaxWave that your account status is still active and current. If you're not in any formal resolution, this notice signals that the IRS has not forgotten the balance and continues to accrue interest (~7–8% annually).

No immediate deadline, but balance continues compounding with interest and penaltiesIRS.gov reference →

CP88Delinquent Return — Current Year Refund Withheld

MediumUnfiled Returns

What it means: You have a refund due on your current-year return, but the IRS has identified one or more unfiled returns from prior years. Under IRC §6402, the IRS has statutory authority to withhold your refund until the delinquent returns are filed and any resulting balance is assessed. The notice specifies exactly which prior year's return is missing.

What to do: File the delinquent return as quickly as possible. If you owe on that year, the IRS will apply your current refund toward the prior-year balance and issue any remainder. If the delinquent year produces a refund or zero balance, your full current-year refund will be released once the return is processed — typically 4–8 weeks after filing.

No fixed deadline, but refund remains entirely withheld until all required returns are filedIRS.gov reference →

CP501First Reminder — Balance Due

MediumBalance Due

What it means: A follow-up reminder that you have an unpaid balance — usually sent 4–6 weeks after the CP14 if no payment or response was received. The balance now includes additional interest accrued since the CP14, and the tone is noticeably more urgent. Enforcement action is still not imminent at this stage, but the IRS account is progressing through the collection sequence.

What to do: Pay in full or contact TaxWave immediately to set up a payment plan. Every notice you ignore adds more accrued interest to the total balance. Setting up a plan at the CP501 stage avoids the more urgent CP503 and the levy-notice CP504 that follow.

Payment due date shown on notice; CP503 follows if no responseIRS.gov reference →

CP503Second Reminder — Balance Due

Medium-HighBalance Due

What it means: The IRS's second escalation reminder — more urgent in tone than the CP501. Sent when neither the CP14 nor CP501 produced a payment or response. At this stage, the IRS account is actively moving toward enforcement-level collection. The next notice — CP504 — initiates formal levy authority and sets the stage for bank account and wage levies.

What to do: Address this immediately. Setting up an installment agreement or entering a resolution at the CP503 stage still prevents escalation to the more serious CP504 enforcement sequence. Contact TaxWave to evaluate your full options — payment plan, OIC, CNC — before the next notice arrives.

Payment due date shown on notice — CP504 follows shortly after if ignoredIRS.gov reference →

CP504Notice of Intent to Levy — State Tax Refund

HighLevy / Enforcement

What it means: The IRS is formally notifying you of its intent to levy your state tax refund under IRC §6331. While this technically authorizes levy of state refunds only at this stage, it is a critical inflection point in the collection sequence. The CP504 signals that the IRS has exhausted normal billing channels and is escalating to enforcement. It is also required by law before the IRS can file a Notice of Federal Tax Lien in many situations.

What to do: Act immediately — do not wait for the LT11. The window between CP504 and the Final Notice of Intent to Levy (LT11) is when TaxWave intervention is most effective. Getting into a payment plan, OIC, or CNC status before the LT11 is issued preserves more options and avoids the more aggressive enforcement that follows a formal levy notice.

No CDP rights yet — but the LT11 (next step) triggers the critical 30-day CDP windowIRS.gov reference →

CP521Installment Agreement Payment Reminder

LowPayment Plans

What it means: A standard monthly reminder that your scheduled installment agreement payment is due. Sent to taxpayers with active payment plans who have not enrolled in direct debit (DDIA). Includes the exact payment amount, the due date, and the current remaining balance on the agreement. This is a routine administrative notice — not a warning.

What to do: Make the payment by the exact due date shown on the notice. Missing even a single installment agreement payment can trigger CP523 (intent to terminate) and eventually default your agreement — which reinstates the IRS's full levy authority. If you cannot make a payment, contact TaxWave before the due date to explore options.

Payment due date on the notice — do not missIRS.gov reference →

CP523Intent to Terminate Installment Agreement

HighPayment Plans

What it means: Your installment agreement is in default and the IRS intends to terminate it. Common triggers: a missed payment, a newly filed return with an unpaid balance (new liability added to the account), failure to file a required return while in the agreement, or missing a required financial review. Termination reinstates the IRS's full levy authority without requiring any additional notice.

What to do: Contact TaxWave immediately. You typically have 30 days from this notice to cure the default — make the missed payment, address the new balance, or file the missing return. If the default cannot be cured, you need to negotiate a new installment agreement or move to an alternative resolution (OIC, CNC) before the IRS resumes enforcement activity.

30 days to respond before the agreement is formally terminated and enforcement resumesIRS.gov reference →

LT11 / Letter 1058Final Notice of Intent to Levy — CDP Rights Triggered

URGENTLevy / Enforcement

What it means: This is the IRS's final statutory notice before it can begin levying your wages, bank accounts, retirement accounts, Social Security, receivables, and other property. Under IRC §6330, this notice formally triggers your Collection Due Process (CDP) rights — your legal right to request a hearing before the IRS Office of Appeals. The 30-day deadline from this notice is one of the most consequential and strictly enforced deadlines in all of tax law.

What to do: File Form 12153 (Request for CDP Hearing) within 30 days by certified mail to the address on the notice. A timely CDP request immediately pauses all levy activity while your case is reviewed by an Appeals Officer. You can propose an installment agreement, OIC, CNC status, or innocent spouse relief at the hearing. Missing this window does not eliminate all rights but permanently waives formal CDP rights and significantly limits your options. Contact TaxWave the same day you receive this.

30 days from notice date — hard statutory deadline for full CDP rightsIRS.gov reference →

Letter 3172Notice of Federal Tax Lien Filing — CDP Lien Rights

HighLiens

What it means: The IRS has filed a Notice of Federal Tax Lien (NFTL) with your county recorder's office or state authority, creating a public record of your federal tax debt. This lien attaches to all of your current and future property — real estate, vehicles, financial accounts, business assets — and can prevent you from selling or refinancing property and may surface in credit and public-record searches. You also have lien-related CDP rights that expire in 30 days.

What to do: Request a CDP hearing within 30 days if you want to formally challenge the lien filing. If your balance is ≤$25,000 and you are current on a Direct Debit Installment Agreement, you qualify for lien withdrawal under the IRS Fresh Start program. TaxWave can also evaluate lien subordination (Form 14134) for refinancing or property sales, or discharge (Form 14135) if you're selling a property the lien is attached to.

30 days to request CDP hearing on the lien filing — separate from any levy CDP rightsIRS.gov reference →

Letter 3219 / 90-Day LetterStatutory Notice of Deficiency

URGENTAudit / Deficiency

What it means: Also called the '90-day letter,' this is the IRS's formal legal notice that it has determined you owe additional tax — typically following an audit examination or the Automated Underreporter process — and will assess that deficiency unless you petition the U.S. Tax Court. This is not a bill — it is the IRS's last required step before assessing a deficiency. You do not have to pay first to contest it in Tax Court.

What to do: Contact TaxWave or a tax attorney immediately. Filing a Tax Court petition within 90 days (150 days if you're outside the U.S.) pauses the entire assessment and preserves all your appeal rights. You can contest the proposed deficiency fully in Tax Court without paying it first. Missing the 90-day deadline permanently waives your Tax Court rights — the deficiency is then assessed automatically and collection begins.

90 days to petition U.S. Tax Court — hard statutory deadline with no exceptionsIRS.gov reference →

CP508CPassport Certification — Seriously Delinquent Tax Debt

HighEnforcement

What it means: The IRS has certified your tax debt as 'seriously delinquent' under IRC §7345 — generally meaning your balance exceeds approximately $62,000 (adjusted annually for inflation) and is not in an approved resolution program. This certification is transmitted to the U.S. State Department, which can then deny passport renewals or applications and may revoke existing passports. The restriction is lifted once the balance enters a qualifying resolution or falls below the threshold.

What to do: Entering an installment agreement, submitting an OIC, or securing CNC status causes the IRS to reverse the certification within approximately 30 days. If you have imminent international travel, document the hardship and contact TaxWave immediately to pursue the fastest available resolution path — an installment agreement can be the quickest way to reverse the certification.

Immediate and ongoing — restriction lifts only when debt enters a qualifying resolutionIRS.gov reference →

Letter 1153Trust Fund Recovery Penalty — Proposed Assessment

URGENTBusiness / Payroll

What it means: The IRS is proposing to assess the Trust Fund Recovery Penalty (TFRP) against you personally for a business's unpaid payroll taxes (Form 941 trust fund balances). The TFRP holds 'responsible persons' personally liable for the employee-side portion of payroll taxes — employee Social Security, Medicare, and withheld income taxes — that were collected but not remitted to the IRS. This personal liability: survives business bankruptcy, cannot be discharged in personal bankruptcy, and can be assessed against multiple responsible persons simultaneously.

What to do: You have 60 days to appeal the proposed TFRP assessment before it becomes final. The primary defenses are: (1) you were not a 'responsible person' with authority over payment decisions, or (2) you did not willfully fail to collect and pay over the taxes. Gather documentation of your role, authority, signing rights, and actual financial control within the business. Contact TaxWave immediately — this 60-day window is critical.

60 days to appeal the proposed TFRP assessment — after that it is assessed and becomes finalIRS.gov reference →

CP259Business Tax Return Not Filed

Medium-HighUnfiled Returns

What it means: The IRS expected a business tax return for the period shown — most commonly Form 941 (quarterly payroll), Form 1065 (partnership), Form 1120 (C corporation), or Form 1120-S (S corporation) — and did not receive it. If the return is not filed, the IRS may prepare a Substitute for Return (SFR) using third-party data alone, which never accounts for deductions, credits, or cost basis — resulting in a dramatically overstated tax assessment that enters the full collection sequence.

What to do: File the return immediately, even if you cannot pay the resulting balance. The failure-to-file penalty (5% per month up to 25%) is five times larger than the failure-to-pay penalty (0.5% per month). For partnerships and S corporations, multiple years of unfiled returns create cascading compliance issues and can trigger TFRP investigations for principals.

File as soon as possible — penalties accrue monthly up to 25% of tax dueIRS.gov reference →

CP2000Proposed Changes — Unreported Income

MediumReturn Changes

What it means: The IRS's Automated Underreporter (AUR) program cross-referenced your return against all third-party income documents filed under your SSN — W-2s, 1099s, K-1s, broker statements, cancellation of debt — and detected a discrepancy. This is a proposed assessment, not a final bill, but it includes proposed additional tax, a 20% accuracy penalty, and interest. Most common triggers: 1099-MISC/NEC freelance income, 1099-B stock sales (especially without reported cost basis), 1099-C cancelled debt (which may be excludable), 1099-R retirement distributions, and K-1 pass-through income.

What to do: Do not pay the proposed amount without a thorough review — many CP2000s can be significantly reduced or eliminated. If income was reported on a different line of your return, document it. If you have offsetting deductions, credits, or cost basis, compile the supporting documentation. You have 60 days to respond before the IRS issues a CP3219A (Statutory Notice of Deficiency). A professional response frequently eliminates the 20% accuracy penalty even when some additional tax is legitimately owed.

60 days to respond before escalation to a Statutory Notice of DeficiencyIRS.gov reference →

CP2501Income Discrepancy Inquiry — Early AUR Stage

MediumReturn Changes

What it means: An early-stage Automated Underreporter inquiry — similar in nature to a CP2000 but earlier in the process. The IRS has detected what appears to be unreported income and is requesting clarification before preparing a formal proposed adjustment. Responding fully at this stage often prevents the more serious CP2000 from being issued at all. This is the most flexible point to resolve an underreporter issue.

What to do: Respond promptly with a clear, documented explanation: the income was reported correctly (with documentation showing where), you have offsetting deductions or cost basis, the income belongs to someone else (e.g., an ex-spouse), or you agree and will file an amended return. Don't miss this early window — it's the least consequential stage to resolve the discrepancy.

60 days to respond — full response here typically prevents escalation to a CP2000IRS.gov reference →

Letter 5071CIdentity Verification Required

MediumIdentity

What it means: The IRS suspects that your Social Security Number may have been used to file a fraudulent tax return — either to claim a refund in your name, or the return shows patterns consistent with identity theft. Your refund is being held and your return will not be processed until your identity is verified. This notice is sent proactively to protect you — the IRS does not want to issue a refund to someone impersonating you.

What to do: Complete verification as quickly as possible: (1) Online at IRS.gov/identity-verification using ID.me — fastest option, typically resolves processing within 24–48 hours; or (2) Call the number on the letter with your current-year return, a prior-year return, and photo ID available. If someone did file fraudulently under your SSN, the IRS will process your legitimate return and reject the fraudulent one. Consider filing an IRS Identity Theft Affidavit (Form 14039) as well.

Respond promptly — your return and any refund are completely paused until identity is verifiedIRS.gov reference →

CP90 / CP297Final Notice Before Levy on Federal Benefits

URGENTLevy / Enforcement

What it means: The IRS is preparing to levy federal benefit payments — primarily Social Security retirement, disability, and survivor benefits — if you do not respond. Like the LT11, this notice triggers formal Collection Due Process (CDP) rights with a strict 30-day deadline. Under the Federal Payment Levy Program (FPLP), the IRS can withhold up to 15% of each Social Security payment. This notice is typically issued to taxpayers on fixed income for whom other collection methods have been exhausted.

What to do: File Form 12153 (Request for CDP Hearing) within 30 days. TaxWave frequently secures Currently Not Collectible (CNC) status for taxpayers who receive Social Security as their primary income — which ends the levy entirely and pauses collection. If your only substantial income is Social Security, CNC status is often the appropriate long-term resolution.

30 days from notice date — hard CDP deadline, same as LT11IRS.gov reference →

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