The fastest way to find your existing IRS CAF number is to locate the original assignment letter the IRS sent when the authorization was first processed, or to pull it from your own prior authorization records. There is no public CAF search database. A tax professional who has misplaced the number can call the official Practitioner Priority Service, where retrieval begins only after authentication. A missing number is not the same as a CAF pending-review hold: during pending review the IRS suspends CAF activity and does not process related forms or requests, including transcripts, with no guaranteed resolution time (IRS guidance).
Where a CAF Number Comes From and Where to Look
A CAF number is a unique nine-digit identifier assigned on the first third-party authorization and communicated in an IRS letter. An individual or entity may have one, and the assigned identifier should be reused on later authorizations rather than treated as something to replace. Your own records are usually the best starting point: the signed Form 2848 or Form 8821 you filed, the copy your client kept, the letter the IRS sent confirming the assignment, or the entry in your firm's practice-management system. If you are preparing or refiling an authorization and need to decide which form fits the work, see Form 2848 vs. Form 8821.
When the paper trail is gone, a tax professional can call the Practitioner Priority Service for help recovering the number, but retrieval begins only after the caller is authenticated. Do not request a new identifier merely because the existing one is forgotten — reuse the assigned number once you find it.
Lost Number vs. Pending Review: Two Different Problems
A lost CAF number and a CAF pending-review hold require different responses. The first is a records problem; the second is an IRS processing status described in the notice you received.
| Situation | What it means | First action | Do not do |
|---|---|---|---|
| Number misplaced, authorization likely on file | The identifier exists but you cannot find it | Search your records and prior filings; call Practitioner Priority Service after authentication | Request a replacement identifier just because you forgot it |
| CAF pending review | IRS suspends CAF activity; related forms and transcript requests are not processed | Follow the actual notice's instructions | Assume a fixed resolution date |
| Number located | You can reuse it on later authorizations | Reuse the assigned identifier | Treat the number itself as proof of current authority or processing |
If a transcript request comes back blocked or a form seems stalled while a CAF matter is under review, check whether the account is in pending review before concluding the authorization failed. A located number does not itself grant authority or prove a form is processed. If you are reconciling the CAF indicator on a transcript with what you actually authorized, IRS Code 960 explains how the indicator is added, updated and reversed.
Practical Recovery Checklist
- [ ] Search your firm's records for the original signed Form 2848 or Form 8821.
- [ ] Look for the IRS letter that first communicated the nine-digit CAF number.
- [ ] Check your practice-management system and any prior authorization copies the client retained.
- [ ] If records are exhausted, call the Practitioner Priority Service; expect authentication before retrieval begins.
- [ ] Once found, reuse the assigned identifier on later authorizations rather than requesting a new one.
- [ ] If a transcript or form request seems stalled, check the account for a CAF pending-review hold before assuming the authorization failed.
- [ ] Follow the actual notice for a pending-review matter; there is no guaranteed resolution time.
Frequently Asked Questions
Is there a public database where I can look up a CAF number?
No. The IRS does not offer a public CAF search. Find the number in your own prior authorization records or the assignment letter, and a tax professional can call the Practitioner Priority Service for recovery help after authentication (IRS guidance).
Should I request a new CAF number if I forgot the existing one?
No. An individual or entity may have one CAF number, assigned on the first third-party authorization, and the assigned identifier should be reused on later authorizations. Requesting a replacement because you forgot the existing one is not the right move.
Does a CAF number prove my authorization is active or that a form was processed?
No. A located number lets you reuse the identifier on later authorizations, but it does not itself grant authority or prove a form is processed. Confirm the underlying authorization and its status separately. If you are dealing with a levy or collection notice that involves an authorization question, IRS LT11 and Letter 1058 covers triaging that specific notice.
If the separate problem is a Letter 5071C identity-and-return verification request, follow that notice’s process; recovering a CAF number does not complete the taxpayer’s verification. The recovery checklist above is a way to organize records, not a new IRS submission requirement.
For tax firms
A tax firm can review how authorization records, CAF identifiers and related client files are organized and who is responsible for each step before a missing number or pending-review hold slows the workflow.
Discuss your firm’s authorization, transcript and CRM workflow in a 26T1 demo.