Quick overview

When the IRS asks for additional information it usually sends a written notice that explains the issue, lists the documents needed, and gives a deadline. Common causes include missing or mismatched 1099s, unsupported deductions or credits, identity verification, or unfiled returns. The notice will indicate whether the IRS proposes changes (e.g., a CP2000) or merely needs clarification (see IRS guidance on responding to correspondence) (IRS.gov).

Below I outline step-by-step actions you can take, how to package your response, your rights and options, and when to seek professional help. In my work as a CPA helping taxpayers respond to IRS notices, prompt organization and a clear cover letter are often the difference between a quick resolution and a drawn-out dispute.

Step-by-step: How to respond

  1. Read the notice immediately. Note the tax year, form, and the deadline. The notice will explain what the IRS believes is incorrect and what documents it wants. Do not assume the notice is a final assessment — it usually requests a response first (IRS, Responding to IRS Correspondence).

  2. Verify identity and authenticity. Confirm the notice is from the IRS (it will include a notice number and contact info). The IRS primarily sends notices by U.S. mail — unexpected phone calls demanding payment can be scams. If the notice mentions identity verification, follow the IRS identity verification instructions or see Form 14039 if you suspect identity theft (IRS.gov).

  3. Match the IRS issue to your records. Identify the specific items the IRS flagged (for example, a missing 1099, questioned charitable deductions, or an unexplained credit). Pull the supporting documents: W-2s, 1099s, receipts, bank statements, canceled checks, and substantiation for credits.

  4. Gather documentation and create a clear cover letter. Your cover letter should:

  • Identify the taxpayer(s) and the tax year(s)

  • Quote the IRS notice number

  • Briefly explain what you are sending

  • List enclosed documents (number and type)

  • Provide a daytime phone number and a request for confirmation of receipt

    Label documents to match the IRS line items. Organized, labeled submissions speed processing and reduce follow-up requests.

  1. Include copies, not originals. Send photocopies of documents. Keep your originals safe; the IRS does not need original receipts in most correspondence audits, but it may request originals later for field audits.

  2. Choose a secure delivery method. Use certified mail with return receipt, an IRS e-filed portal when applicable, or an IRS-designated secure upload site if the notice instructs you to upload documents. Keep proof of the date you mailed or uploaded everything.

  3. Submit a tax pro authorization if someone else is responding for you. If you hire a CPA, attorney, or enrolled agent, file Form 2848 (Power of Attorney) so the IRS can discuss the case with your representative (IRS, Form 2848).

  4. Track follow-up and keep records. Log each communication — date sent, delivery method, and who you spoke with at the IRS. Keep copies of everything for at least three years (longer if the issue involves unreported income or a loss).

What you can expect after you respond

  • The IRS will review your documents. Processing times vary: simple correspondence items can be resolved in a few weeks; complex cases or those requiring research can take months.
  • If the IRS accepts your documentation, it will send a closing letter explaining no change or final correction.
  • If the IRS still believes a change is necessary, it will send a proposed adjustment or a notice of deficiency and explain appeal rights (you may have 30 days to petition the U.S. Tax Court or 60 days if outside the U.S.; check the notice for exact deadlines).

Common document requests and how to respond

  • Missing or mismatched income (W-2s/1099s): Provide copies of all relevant 1099s/W-2s, and if a payer didn’t issue a 1099, produce bank records or checks proving payment.
  • Unsupported deductions (charitable donations, business expenses): Supply receipts, canceled checks, bank statements, mileage logs, and contemporaneous records that substantiate the expense.
  • Credits (earned income tax credit, child tax credit): Provide supporting eligibility documentation such as birth certificates, school records, or proof of residency.
  • Unfiled returns: Prepare and file the missing return(s) immediately and send the IRS a copy or proof of filing.
  • Identity verification: Follow instructions exactly; you may be asked to use an online tool or to submit Form 14039 if you suspect identity theft (IRS.gov).

Practical tips that help (from practice)

  • Start with the simplest items first. Satisfy requests for a missing 1099 or simple receipt quickly — these often close the case.
  • Use a one- or two-page cover letter that maps your documents to the IRS notice line items. Don’t let the IRS hunt through a folder trying to find what you referenced.
  • If an amount is a math error and you agree, sign the form the IRS provides and return it to stop further action.
  • If you can’t find a document, assemble alternative evidence (bank records, third-party statements) and explain what you searched for and why the original is unavailable.

When to accept, when to dispute

  • Accept when the IRS position is supported by clear documentation or when the amount due is small relative to the cost of contesting it.
  • Dispute when you have strong documentation, credible third-party evidence, or a legal basis to challenge the IRS’s interpretation. If you disagree with a proposed adjustment you can: communicate in writing, request an appeals conference with the IRS Independent Office of Appeals, or pursue the matter in Tax Court if eligible (IRS, Appeals).

For guidance on preparing organized documentation for a possible audit, see our checklist: Preparing for an IRS Audit: Documentation Checklist (https://finhelp.io/glossary/how-to-prepare-for-an-irs-audit-documentation-checklist/).

For recordkeeping best practices that reduce audit risk, see: Essential Records to Keep for Filing and Audit Readiness (https://finhelp.io/glossary/essential-records-to-keep-for-filing-and-audit-readiness/).

If your case escalates to an audit or complicated dispute, these articles explain documentation and defense strategies: Building an Audit Defense: Document Preparation and Communication Tips (https://finhelp.io/glossary/building-an-audit-defense-document-preparation-and-communication-tips/).

Deadlines, penalties, and collection risks

Always check the notice for deadlines and instructions. Missing a deadline can lead to: proposed assessments becoming final, penalties and interest accruing, or IRS collection actions (levies, liens). If you need more time because you’re gathering records or arranging representation, call the phone number on the notice and request an extension; the IRS will sometimes grant extra time.

If the IRS issues a proposed assessment and you cannot pay immediately, consider asking for an installment agreement or a temporary delay in collection. The IRS publishes payment options online and will work with taxpayers experiencing hardship.

When to hire a professional

Hire a tax pro (CPA, enrolled agent, or tax attorney) when:

  • You don’t understand the notice or the documentation requested.
  • The amounts involved are large or could trigger penalties.
  • The IRS is moving toward collections or a formal examination.
  • You prefer a representative to manage communications (file Form 2848 to authorize representation).

In my practice, cases where taxpayers had neat, labeled packages and a short explanatory cover letter almost always resolve faster than disorganized submissions.

Common mistakes to avoid

  • Ignoring the notice.
  • Sending unspecified bundles of documents without a cover letter.
  • Mailing originals rather than copies.
  • Failing to track delivery or keep a log of communications.

Sample short cover letter (adapt to your situation)

[Your name]
[Your address]
[Date]

IRS
[Address on notice]

Re: Notice number [XXXXXX] — Tax Year [YYYY]

Enclosed please find documents responsive to the IRS notice dated [date]. The enclosed items are listed below:

  • Copy of Form W-2 from Employer X (1 page)
  • Copy of Form 1099-MISC from Payer Y (2 pages)
  • Receipts for charitable donations (5 pages)

If you need additional information, please contact me at [phone] or my authorized representative [name and phone]. Please confirm receipt of these materials.

Sincerely,

[Signature]

Final notes and authoritative resources

This article is educational and not a substitute for personalized tax advice. For official IRS guidance, see: Responding to IRS Correspondence (https://www.irs.gov/faqs/irs-procedures/responding-to-irs-correspondence) and the Taxpayer Bill of Rights (https://www.irs.gov/taxpayer-bill-of-rights). For form references visit IRS pages for Form 2848 (Power of Attorney) (https://www.irs.gov/forms-pubs/about-form-2848) and Form 14039 (Identity Theft Affidavit) (https://www.irs.gov/forms-pubs/about-form-14039).

If you’d like help drafting a response or organizing documents, consult a qualified tax professional to review your notice and represent you if needed.

Disclaimer: This content is for educational purposes and does not constitute legal, tax, or financial advice. Prices, procedures, and IRS policies may change; check the IRS website or consult a professional for current information.