How to Apply for a CAF Number: Forms 2848 and 8821

There are two ways to apply for a CAF number: register through the IRS Tax Pro Account online, which can assign one immediately, or submit your first Form 2848 or Form 8821 for a client and receive the number when the IRS processes that form. The CAF (Centralized Authorization File) number is a nine-digit identifier the IRS uses to track your authority to represent taxpayers or receive their tax information.¹ The online route is faster; the paper route is what you use when the online tool doesn’t cover your situation.

Who Needs a CAF Number

Any tax professional who files a third-party authorization with the IRS gets a CAF number. That covers attorneys, CPAs, enrolled agents, enrolled actuaries, and enrolled retirement plan agents, all of whom can request full power of attorney.²

Unenrolled return preparers can also receive a CAF number, but their representation rights are limited. They can only represent clients during an examination of a return they personally prepared and signed, and only before revenue agents, customer service representatives, and similar IRS employees, not appeals officers, revenue officers, or Office of Chief Counsel attorneys. For returns prepared after 2015, they must also hold a valid Annual Filing Season Program Record of Completion for both the year the return was prepared and the year representation occurs.³ An unenrolled preparer who doesn’t meet those requirements can still file Form 8821 to receive a client’s tax information but has no representation authority.⁴

A CAF number exists only for acting on behalf of someone else. Individuals handling their own tax matters don’t need one, and it is separate from your TIN, EIN, or PTIN.¹

Applying Through the Tax Pro Account

The Tax Pro Account on IRS.gov is the fastest option. The IRS added functionality that lets tax professionals request and receive a CAF number entirely online, with no form to complete and no wait for mail.²

You’ll verify your identity through ID.me. That means uploading a photo of a government-issued ID (driver’s license, state ID, or passport) and taking a selfie with a smartphone or webcam. If you already have an ID.me account from another government service, sign in with those credentials. Once you’re verified, the system can assign the number right away.

Two limits are worth knowing before you rely on this route. The Tax Pro Account only handles authorizations for individual taxpayers, not businesses, and the client must have a U.S. address and be able to sign in to their own IRS online account to approve your authorization request.² If your first client is a business, or if they can’t access an online account, use the form route instead.

Applying by Form 2848 or Form 8821

The traditional path is to submit Form 2848 (Power of Attorney and Declaration of Representative) or Form 8821 (Tax Information Authorization) for your first client. The IRS assigns your CAF number when it processes that initial form.

Filling In Your Information

The form asks for your name, business address, phone number, and professional designation (attorney, CPA, enrolled agent, and so on). You also provide your jurisdiction state and the associated license, bar, certification, or enrollment number, plus your PTIN if you have one.⁵

In the CAF number field, write “NONE.” The IRS will issue the number to you after processing.⁶

Common Reasons the IRS Rejects the Form

Getting rejected means starting over, so watch for these before you submit:⁷

Missing signatures or dates from either the taxpayer or the representative.
Vague tax periods on Line 3. Writing “all years” or “all future periods” will get the form kicked back. List specific years or ranges, such as “2023 through 2025.”
Missing professional designation or jurisdiction state.
Missing license, bar, CPA certification, or enrollment number.
Checking the retention box on Line 6 without attaching the prior power of attorney you want to keep in place.

Signatures

If you submit online, the IRS accepts several forms of electronic signature: a typed name in the signature block, a scanned image of a handwritten signature, input from an electronic signature pad or stylus, or a signature generated by third-party software.⁸ If you have no prior personal or business relationship with the taxpayer and they sign electronically in a remote transaction, the IRS requires additional identity authentication for the taxpayer.

Fax and mail submissions do not accept electronic signatures. Those forms need a wet ink signature.

Submitting the Form

Pick one submission method. Sending the same form through more than one channel can cause processing delays.⁸

Online Upload

The IRS provides an upload tool on IRS.gov for completed Forms 2848 and 8821. Sign in or create an account, answer a few questions about the form, and upload the file. Accepted formats are PDF, JPG, or GIF, with a 15 MB limit. Save any attachments together with the form in a single file. Submit only one form at a time, even for married couples filing jointly; each form is tied to a single taxpayer identification number, and bundling multiple forms leads to rejection of the extras.⁸

You’ll get an email confirming receipt. The IRS does not send a separate notice when processing finishes, so check the processing status tool on IRS.gov or your active authorizations in Tax Pro Account.

Fax

Fax the form to the CAF unit that handles your client’s location:⁵

Ogden CAF Unit, 855-214-7522: Alaska, Arizona, California, Colorado, Hawaii, Idaho, Iowa, Kansas, Minnesota, Missouri, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, Wisconsin, and Wyoming.
Memphis CAF Unit, 855-214-7519: Alabama, Arkansas, Connecticut, Delaware, District of Columbia, Florida, Georgia, Illinois, Indiana, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Mississippi, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, South Carolina, Tennessee, Vermont, Virginia, and West Virginia.
Philadelphia CAF Unit, 855-772-3156: all APO/FPO addresses, American Samoa, Guam, U.S. Virgin Islands, Puerto Rico, and foreign countries.⁶

Mail

Mail addresses follow the same geographic split:⁵

Ogden: Internal Revenue Service, 1973 Rulon White Blvd., MS 6737, Ogden, UT 84201
Memphis: Internal Revenue Service, 5333 Getwell Road, Stop 8423, Memphis, TN 38118
Philadelphia: Internal Revenue Service, International CAF Team, 2970 Market Street, MS 4-H14.123, Philadelphia, PA 19104

After the IRS Assigns Your Number

Once the IRS processes your first authorization, the CAF number is linked to your record. The IRS does not typically send a separate letter containing only the number. Processing times vary, and faxed or mailed submissions can take several weeks.

From that point on, enter your CAF number on every Form 2848 and Form 8821 you file. That tells the IRS to add each new authorization to your existing file rather than opening a duplicate record.⁶

If you forget the number, sign in to your Tax Pro Account to look it up,² or call the Practitioner Priority Service at 866-860-4259 and a representative will verify your identity and retrieve it.⁹

1
Internal Revenue Service. What Is a CAF Number
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Internal Revenue Service. Tax Pro Account
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Internal Revenue Service. Instructions for Form 2848 (09/2021)
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Internal Revenue Service. Annual Filing Season Program
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Internal Revenue Service. Instructions for Form 2848 (Rev. September 2021)
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Internal Revenue Service. The Centralized Authorization File (CAF) – Authorization Rules
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Internal Revenue Service. Common Reasons for Power of Attorney (POA) Rejection
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Internal Revenue Service. Submit Forms 2848 and 8821 Online
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Internal Revenue Service. Practitioner Priority Service