You signed Form 2848 today. You gave your accountant power of attorney to contact the IRS on your behalf. And yet, when he calls to resolve something urgent, the IRS tells him they can't do anything yet. The reason is almost never the form you signed: it's the CAF file , an administrative step that hardly anyone talks about until they run into it at the worst possible moment.
What is the CAF number?
CAF stands for Centralized Authorization File, the centralized system the IRS uses to keep track of who is authorized to speak or act on behalf of which taxpayer. When someone—you, your accountant, an attorney—first files a third-party authorization with the IRS, either a Form 2848 (Power of Attorney) or a Form 8821 (Tax Information Authorization), the IRS assigns that person a unique 9-digit CAF number .
That number is not your business's EIN, your accountant's Social Security Number, or their PTIN (President Taxpayer Identification Number). It's a separate identifier, specific to the authorization system, and once your accountant is assigned that same CAF number, it's used for all future authorizations they receive from any client.
The most common misconception: signing is not activating
Here's the most frustrating part: signing Form 2848 doesn't trigger anything immediately. The signed document is just the first step. The IRS then has to receive, review, and process it to link it to the representative's CAF number—and that processing, when submitted by mail, can take up to six weeks.
This means that if you sign the power of attorney on the same day you need your accountant to call the IRS about an urgent matter—a notification, an audit, a problem with a deposit—it almost certainly won't be useful in time. The IRS doesn't yet have a record that this person is authorized to speak on your behalf, no matter how many signed copies you have.
Why the IRS recommends filing the power of attorney months in advance
Precisely because of this processing time, the IRS recommends filing a power of attorney (POA) at least 16 weeks in advance of when you actually need your representative to act on your behalf. This might sound excessive until you understand the context: between the volume of forms the IRS processes, mailing times, and potential corrections if something on the form is incomplete, 16 weeks is the margin that reduces the risk of being left without representation precisely when you need it most to almost zero.
In practice, this changes the way you should think about your relationship with your accountant or tax representative: it's not something you activate when a problem arises, it's something you leave running in the background, active and current, before any emergency appears.
The scenario no one expects: "pending review"
There is a third obstacle that further complicates matters. The CAF number may be placed on " pending review " for identity theft protection. The IRS has strengthened these controls in recent years precisely because the CAF system, by centralizing who can act on behalf of whom, is an attractive target for fraud.
While a CAF number is in that review state, all processing associated with it is suspended . It's not that processing is slower; nothing is processed at all. Neither the new 2848 form you just signed, nor any previous applications linked to that number. If your accountant hasn't recently checked the status of their own CAF, they could be operating—unknowingly—with a number that is effectively frozen.
The practical conclusion
All of this boils down to one simple idea, but one that very few businesses implement: signing Form 2848 on the same day you need your accountant to call the IRS is useless . Your representative's CAF number must be active and fully processed beforehand. That means asking your accountant or tax representative directly if their CAF is valid, checking it periodically—not just the first time you start working together—and submitting any new authorizations months, not days, in advance.
What to do if you're about to change your meter
Each time you authorize a new representative for the same matters and tax periods, that new authorization automatically revokes the previous one. It's a good time to review the entire situation: confirm that the new accountant has an active CAF number, file the corresponding 2848 or 8821 form well in advance, and don't assume that just because you signed the document, everything is resolved.
A simple habit that prevents the problem
The easiest way to avoid being caught is to make this verification part of your annual routine with your accountant, not something you only investigate when there's an emergency. Ask directly, "Is your CAF number active and unrestricted?" at the start of each tax season, and keep written records of the date you filed any Form 2848 or 8821. That small administrative habit is what separates a business that can react quickly to the IRS from one that waits for weeks when time is at a premium.
FAQ
Does Form 8821 also require a CAF number?
Yes. Both 2848 (Power of Attorney) and 8821 (Tax Information Authorization) generate or use a CAF number for the designated person, although 8821 only authorizes viewing information, not actively representing you.
Can I check if my meter's CAF is active?
Your accountant can check the status of your CAF number directly with the IRS. If they've never done so, it's worth asking, especially before a busy tax season.
What happens if I file form 2848 online instead of by mail?
The IRS's electronic options can reduce processing time compared to traditional mail, but they don't eliminate it entirely, so the recommendation to plan ahead still applies.
Does the CAF number change if I change the meter?
No. The CAF number belongs to the representative (your accountant), not to you as the taxpayer. If you change accountants, the new representative will use their own CAF number, which may already exist if they previously represented other clients.
Don't leave your representation to the last minute
The CAF file is one of those administrative details that goes unnoticed until it becomes an urgent problem. If your business is still unclear about who is authorized to communicate with the IRS on your behalf, or if you're unsure whether that authorization is actually active, it's time to review it before the next notice arrives.
Request your free quote here and we'll review together what your business needs to be protected from the IRS.
Fuente: IRS — What is a CAF number.
Also read: Form 8822-B: Notify the IRS that your address or responsible party has changed · Franchise tax, sales tax, and income tax: The 3 taxes every business owner should understand · Form 966: How to close your corporation step by step · How long to keep your paperwork when closing your business · BOI scam: How to recognize fake FinCEN letters.
