en An official website of the United States Government (NON-Prod - Development Environment)
Popular search terms:

Letter 4800 C, Questionable Credit 30 Day Contact Letter

View our interactive tax map to see where you are in the tax process. It could help you navigate your way through the IRS.

Show on Roadmap

Letter Overview

Letter 4800C is mailed to taxpayers informing them that the IRS is proposing a deficiency or disallowing a claim for refund or a credit for a subsequent period’s estimated tax.

This notice or letter may include additional topics that have not yet been covered here. Please check back frequently for updates.

What does this letter mean to me?

Based on the information reported to the IRS under your name and Social Security number (SSN) by employers, banks, and other payers, you may need to verify tax credits claimed, income tax withholding, or business expenses before your refund will be released or applied as an overpayment to next year’s estimated tax.

You must respond within 30 days from the date of this letter, or the proposed changes will be made to your account changing the amount of your refund. If you don’t respond within the 30 days as required, then after the suspense period, the IRS will send either a Letter 3219C, Statutory Notice of Deficiency, allowing the taxpayer 90 days to petition the Tax Court, or a Letter 0105C, Claim Disallowed, or a Letter 0106C, Claim Partially Disallowed, and will make an immediate adjustment reflecting the claim disallowance.

How did I get here?

While processing your tax return, an attempt was made to verify wages, withholding, and refundable credits, such as the Premium Tax Credit or the American Opportunity Tax Credit, that were reported to the IRS. The IRS records do not match up with the amounts you reported; therefore, the IRS is proposing adjustments to certain items on your return, e.g., your wages, withholding, and refundable credits. Adjusting your wages may also adjust your refundable credits claimed, such as the Earned Income Tax Credit or the Additional Child Tax Credit.


What are my next steps?


Check the return address

The first thing to do is to check the return address to be sure it’s from the IRS and not another agency.


If you didn’t file

Call the IRS immediately as you may be a victim of tax-related identity theft. Someone else may have used your personal information to file this return.

Note: Authorized third parties may assist taxpayers, but the taxpayer must be present on the phone or in-person.

Complete and send the IRS a Form 2848, Power of Attorney and Declaration of Representative, to authorize someone (such as an accountant) to contact the IRS on your behalf.


If You Filed a Return

To support the entries on your return and complete processing of your tax return you may need to submit documents and information requested in the Letter 4800C, for example:

  • Copies of periodic pay statements or check stubs clearly identifying dates of your employment and the gross income received and withholding deducted.
  • A letter from the employer on company letterhead or stationery showing dates of your employment and the gross amount of wages paid and withholding deducted.
  • §  A copy of your Form 1095-A, Affordable Insurance Marketplace Statement, or documents showing proof that you or your family enrolled in health coverage through the Health Insurance Marketplace.
  • For tuition paid during the taxable year, photocopies of cancelled checks, receipts for tuition, fees and books, or transcripts from the educational institution. You can also submit a list of the classes you took showing the payments you made or documents showing that you were enrolled in a postsecondary school program.

Do Not file a Form 1040-X , Amended U.S Individual Income Tax Return, at this time. Your account will be corrected based on the review of documents submitted.

The review process could take anywhere from 45 to 180 days. If you have not received your refund or heard from the IRS after that time, contact the IRS at the toll-free number listed at the top right corner of your notice.

If the IRS accepts your documentation, the IRS will send you a letter stating that it accepts your return as filed. If your documentation is not accepted, you will receive a letter explaining why. If you disagree, you may request a conference with the IRS Independent Office of Appeals (Appeals).

If you disagree, in the enclosed envelope, send the statement and photocopies of your original documents that support your position. If you’re unable to verify an amount you claimed, explain the issue and how you determined the amount. Include the Response Form or a complete copy of this letter.

If you have submitted all of your documentation and do not agree with the proposed changes to your account, request your case be forwarded to Appeals for review.

If you agree with the proposed changes to your account, sign and return the enclosed form. You will receive a bill advising you of the amount owed. The amount owed will include interest and penalties that will continue to accrue until the balance is paid in full.

If the IRS doesn’t accept the documentation submitted, you will receive a letter explaining why. If you disagree with the decision, you may request an Appeals conference. Appeals is independent from the IRS office that sent you this letter. If you don’t wish to appeal or you disagree with the Appeals decision, you may have the right to take your case to court.

Where can I get additional help?

Understanding your notice or letter

Get Help topics

Browse common tax issues and situations at TAS Get Help

If you still need help

The Taxpayer Advocate Service is an independent organization within the IRS that helps taxpayers and protects taxpayers’ rights. We can offer you help if your tax problem is causing a financial difficulty, you’ve tried and been unable to resolve your issue with the IRS, or you believe an IRS system, process, or procedure just isn’t working as it should. If you qualify for our assistance, which is always free, we will do everything possible to help you.

Visit dev.taxpayeradvocate.irs.gov or call 1-877-777-4778.

Low Income Taxpayer Clinics (LITCs) are independent from the IRS and TAS. LITCs represent individuals whose income is below a certain level and who need to resolve tax problems with the IRS. LITCs can represent taxpayers in audits, appeals, and tax collection disputes before the IRS and in court. In addition, LITCs can provide information about taxpayer rights and responsibilities in different languages for individuals who speak English as a second language. Services are offered for free or a small fee. For more information or to find an LITC near you, see the LITC page on the TAS website or Publication 4134, Low Income Taxpayer Clinic List.