If you’ve lost track of your CAF number, you have three reliable ways to find it: pull up any Form 2848 or Form 8821 you’ve already filed, sign in to the IRS Tax Pro Account, or call the Practitioner Priority Service at 866-860-4259. The number is assigned to you personally the first time you file a third-party authorization, and it stays the same for the rest of your career, so it’s on record somewhere.
Check Your Prior Authorization Forms First
Your own files are the fastest place to look. Your CAF number appears in the representative information section of every Form 2848 (Power of Attorney and Declaration of Representative) and every Form 8821 (Tax Information Authorization) you’ve submitted. Because the IRS ties the number to you rather than to a specific client or matter, the same nine digits appear on every authorization you’ve ever filed.1Internal Revenue Service. The Centralized Authorization File (CAF) – Authorization Rules
If you work in a firm, ask administrative staff. Many practices keep a central list of CAF numbers for their representatives. The IRS also mails a letter confirming the assigned number after your first authorization is processed, so that original letter may be sitting in your files as well.2Internal Revenue Service. What Is a CAF Number?
Look It Up in Tax Pro Account
Tax Pro Account is the IRS self-service portal for practitioners. Once your CAF number is linked to your profile, you can see it along with your active powers of attorney and tax information authorizations, submit new authorization requests, and withdraw existing ones.3Internal Revenue Service. Tax Pro Account
To use the account, you first verify your identity through ID.me. That process asks for a government-issued photo ID, a video selfie, and personal information. The same credentials then work across other IRS online services. Your CAF number has to be in good standing for the account to function properly.4Internal Revenue Service. Tax Professionals Can Access Useful Tools on Their IRS Tax Pro Account
The first time you sign in, you link your existing CAF number to your profile. It’s a one-time step. If you’re linking during an authorization request, the address you enter must match the address the IRS currently has on file for your CAF record. A mismatch will stall the request.3Internal Revenue Service. Tax Pro Account
Call the Practitioner Priority Service
If your own records are empty and you’d rather speak with someone, call the Practitioner Priority Service (PPS) at 866-860-4259. PPS is the IRS support line for tax professionals, and retrieving a forgotten CAF number is one of the things its representatives handle.5Internal Revenue Service. Practitioner Priority Service
The phone menu splits by account type. Press 2 for individual taxpayer accounts or 3 for business accounts; either option routes you to the PPS Account Services team that handles lost or forgotten CAF numbers. There isn’t a separate CAF prompt. PPS is open weekdays, 7 a.m. to 7 p.m. local time, with Alaska and Hawaii on Pacific time.5Internal Revenue Service. Practitioner Priority Service
What You’ll Need to Verify Your Identity
The IRS won’t hand over your CAF number until it confirms who you are, whether you’re on the phone or online. Have this ready before you start:
- Your full legal name as it appears in IRS records
- Your Social Security Number or ITIN
- The mailing address the IRS has on file for you
- Your date of birth
You may also be asked for information from a prior-year return, such as adjusted gross income, as an extra check. Pulling these details together first is worth the minute it takes. PPS hold times run long during filing season, and losing a 40-minute wait because you couldn’t answer a verification question is avoidable.6Internal Revenue Service. Instructions for Form 8821 (09/2021)
If Your Address Has Changed
Because verification checks your address, an outdated one can block you from linking your CAF number in Tax Pro Account and can cause new authorization forms to be rejected. Your CAF address does not update automatically when you move. Two ways to fix it:
- File a new Form 2848 or Form 8821 with the address change box checked and the current address, phone, and fax entered.
- Send a signed, dated letter with your new address to the IRS office where you previously filed your authorization forms. Mail or fax works.
Tax Pro Account does not currently let you change your address through the portal, so one of the two methods above is necessary.3Internal Revenue Service. Tax Pro Account
If You’ve Never Been Assigned a CAF Number
Nothing to find in that case, so you request one. The quickest route is Tax Pro Account, which will issue a CAF number directly without a paper form. The other option is to submit a paper Form 2848 or Form 8821 and write “None” in the CAF number field. The IRS processes the authorization and mails you a letter with your new number.7Internal Revenue Service. Instructions for Form 2848
Paper authorizations are worked first-in, first-out, with a target turnaround of five business days.8Internal Revenue Service. Processing Timeliness: Cycles, Criteria and Critical Dates Online requests submitted through Tax Pro Account are typically processed within 48 hours once the taxpayer approves them.4Internal Revenue Service. Tax Professionals Can Access Useful Tools on Their IRS Tax Pro Account
If You Think Someone Else Has Been Using It
If the reason you’re looking is that something feels off, treat it as urgent. Call PPS at 866-860-4259 to report suspected misuse. Have your name, contact information, CAF number, and the date you noticed the activity ready. A number confirmed as compromised gets flagged in IRS systems to block further authorizations under it.9Internal Revenue Service. 21.3.7 Processing Third-Party Authorizations Onto the Centralized Authorization File (CAF) Once you have the number back, keep it as protected as your Social Security Number and share it only with people who need it for a legitimate filing.5Internal Revenue Service. Practitioner Priority Service