IRS Notice Response Calculator β CP2000, CP504, LT11
Calculate the total amount owed from IRS notices including additional tax, 20% accuracy penalty, and daily interest. Get response deadlines and dispute guidance.
$
Proposed additional tax (before penalties/interest) $
What you believe you actually owe (0 if full dispute) Shown on your notice (typically 60 days for CP2000)
Date printed on your notice
$0
Total Exposure
$0
20% Accuracy Penalty
$0
Interest Accrued
0
Days to Respond
Notice Analysis
Response Options
Understanding IRS Notices
IRS notices are numbered and each has a specific meaning. Understanding which notice you received determines how urgently you need to respond and what your options are.
Notice Urgency Levels
CP14: First bill β 21 days to pay or contact IRS
CP2000/CP2501: Proposed change β 60 days to respond
CP504: Final notice of intent to levy β 30 days before seizure
LT11: Final notice before levy on wages β respond immediately
CP2000/CP2501: Proposed change β 60 days to respond
CP504: Final notice of intent to levy β 30 days before seizure
LT11: Final notice before levy on wages β respond immediately
Interest Calculation
Interest formula (IRS charges daily compound):
Daily rate: 7% / 365 = 0.01918%/day
Interest = Principal Γ (1 + 0.07/365)^days β Principal
On $5,000 unpaid for 365 days: ~$362 in interest
On $5,000 unpaid for 730 days: ~$735 in interest (compounding)
Daily rate: 7% / 365 = 0.01918%/day
Interest = Principal Γ (1 + 0.07/365)^days β Principal
On $5,000 unpaid for 365 days: ~$362 in interest
On $5,000 unpaid for 730 days: ~$735 in interest (compounding)
Extended
Response Letter Guide & Dispute Options
How to respond to each notice type and dispute incorrect IRS figures
Response Letter Templates & Dispute Guide
CP2000 Step-by-Step Dispute Process
- Review the notice carefully β identify which 1099/W-2 the IRS says you omitted
- Check your original return β did you actually report the income? (It may be on a different line)
- Gather documentation β the 1099, your original return, and any offsetting deductions or basis
- Complete the CP2000 response form β included with the notice; circle your response (agree/disagree)
- If disagreeing β write a clear explanation. Example: "The $8,000 on 1099-B represents proceeds. My cost basis was $7,500, resulting in only $500 of taxable gain, not $8,000."
- Attach supporting documents β brokerage statements, original 1099, amended return if needed
- Send via certified mail β keep the receipt; allow 8β12 weeks for IRS response
When to Hire a Tax Professional
- The proposed amount exceeds $5,000
- You received a CP504 or LT11 (enforcement is imminent)
- The notice involves complex issues (business income, investments, foreign accounts)
- You need to negotiate an Offer in Compromise or Installment Agreement
- You believe the IRS is wrong but you lack documentation to prove it
IRS Contact Numbers
- General: 800-829-1040
- Business: 800-829-4933
- Collections (levy/lien): 800-829-7650
- Taxpayer Advocate Service (hardship): 877-777-4778
Frequently Asked Questions
What is a CP2000 notice and do I have to pay?
A CP2000 is an automated IRS "math error" matching notice β not a bill. The IRS computers matched your return against third-party information (W-2s, 1099s) and found a discrepancy. You have 60 days to respond. You can: (1) agree and pay the proposed amount, (2) partially agree by providing corrections, or (3) disagree entirely by explaining why the IRS figures are wrong. A CP2000 is a proposal, not a final assessment.
What is the 20% accuracy-related penalty?
If the IRS determines you underpaid tax due to negligence, disregard of rules, or substantial understatement (25%+ of income), they add a 20% accuracy-related penalty on the underpaid amount. For example, if you owe $5,000 in additional tax, the penalty is $1,000. You can avoid this penalty by showing reasonable cause for the error β being unaware of a 1099, relying on your employer's information, or following professional advice.
How does IRS interest work on CP2000 and notice balances?
IRS interest accrues daily from the original return due date (April 15, 2025 for 2024 taxes) on any underpayment. The rate is the federal short-term rate + 3%, currently about 7% annually (compounded daily). Interest is not waivable and is not a penalty β it is the cost of using the government's money. As of April 2026, roughly 12 months of interest would have accrued on a 2024 return.
What happens if I ignore a CP504 or LT11 notice?
CP504 is the "Final Notice of Intent to Levy" β a serious escalation. If you ignore it, the IRS can seize bank accounts, wages (wage garnishment), and other property. LT11 is the "Final Notice Before Levy on Wages" β after this, the IRS can immediately begin garnishing wages. Respond within 30 days. You can request a Collection Due Process (CDP) hearing within 30 days to pause enforcement while your case is reviewed.
What is the difference between a levy and a lien?
An IRS lien is a legal claim against your property (it does not take the property, but it attaches to it). A levy is the actual seizure of property or income β bank accounts, wages, or other assets. A lien is recorded publicly and affects your credit and ability to sell property. A levy is the action of actually taking money. Responding to notices before levy action is critical to preventing both.