How to Reply to an IRS Notice by Mail

Identify the Notice Number First

The IRS notice number appears in the top right corner or bottom right corner of the letter. It's a five-digit code that tells you what the notice is about—and the IRS system depends on you including it in your reply. Write this number down before you do anything else. The notice itself will also tell you the deadline for responding and what the IRS is asking for. Read that section carefully, because different notices require different responses.

Use the Reply Address on the Notice

The notice includes a reply address, usually printed at the bottom or on a separate instruction page. Use that address, not a general IRS office address. The IRS routes mail by notice type, and sending it to the wrong location delays processing. If the notice does not include a reply address, check IRS.gov or call the number on the notice to confirm where to send your response.

Include the Required Documentation

Your reply should include:

• A copy of the notice itself, or the reply stub attached to it
• Your name and SSN or TIN on every page you send
• A clear, written explanation of your response (if one is required)
• Any supporting documents the notice asks for
• Your current mailing address and phone number

The IRS uses the notice number and your identifying information to match your reply to the correct account. If you omit your SSN or TIN, your response may not reach the right file.

Understand Signature Requirements

Some IRS forms must be signed in ink. If the notice requires a specific form—such as a consent form or a power of attorney—check whether the IRS accepts a printed signature or requires an original ink signature. A printed copy of a signed document does not satisfy this requirement. The notice or IRS.gov will specify what is acceptable. If you are unsure, contact the IRS before sending your reply.

Keep a Copy of Everything

Make a copy of your complete response before you mail it. Keep that copy, along with the original notice, in your records. If the IRS later claims they did not receive your reply, you will have proof of what you sent.

Mailed Replies Have No Proof of Delivery Without Certification

A standard letter mailed through USPS First-Class Mail has no tracking number and no proof of delivery. If you need proof that the IRS received your reply, send it via USPS Certified Mail. Certified Mail provides a tracking number and a record that the letter was delivered to the address on the envelope. This does not prove the IRS opened it or processed it, but it does prove the letter arrived.

Some IRS notices require a response by a specific date. If you are close to that deadline, Certified Mail is worth the extra step—it protects you if there is a dispute about whether the IRS received your response on time.

What You Should Not Do

Do not send your reply to the IRS office where you filed your return or where you normally correspond with the IRS. Use the address on the notice. Do not assume a printed form is acceptable if the notice says "sign in ink"—contact the IRS first. Do not mail your reply without keeping a copy.

Next Steps

The notice itself contains the specific instructions for your situation, including what documents to include and when to send them. Read the notice completely before preparing your reply. If the instructions are unclear, call the number on the notice or visit IRS.gov. The IRS also publishes guidance for specific notice types, and that guidance is the authority for what you need to do.

Mailing a reply is straightforward if you follow the notice's instructions and keep records. The key is matching the notice number to the reply address and including your identifying information on every page.