How to Fax Form 2848 and Form 8821 to the CAF Unit
These are the two forms that let somebody else deal with the IRS about your tax matters, and they are among the small set the IRS genuinely wants by fax. The complication is not the forms themselves, it is working out where to send them, because the destination depends on which side of a river you live on.
📌 The routing rule, straight from the IRS: all states west of the Mississippi process authorizations in Ogden, and all states east of the Mississippi process in Memphis. There are three exceptions. Louisiana and Arkansas process in Memphis despite sitting west. Wisconsin processes in Ogden despite sitting east. International authorizations process in Philadelphia.
Which Form You Actually Need
They are not interchangeable, and picking the wrong one wastes weeks.
Form 2848, Power of Attorney and Declaration of Representative, authorizes someone to represent you before the IRS and act on the tax matters you list. They can speak for you, negotiate, and receive correspondence. It is limited to people qualified to represent taxpayers: attorneys, CPAs, enrolled agents, and certain others.
Form 8821, Tax Information Authorization, only lets a designee inspect or receive your confidential tax information. It grants no authority to represent you or act on your behalf at all. If someone simply needs to see your records, a mortgage lender verifying income for example, 8821 is the lighter and more appropriate option, and it is not restricted to credentialed professionals.
Both go to the same CAF units and the same numbers.
The Signature Rule That Catches People
A faxed Form 2848 needs a handwritten signature in ink. A typed name in a PDF field, or a digital signature applied in software, is not the same thing and will get the authorization rejected.
The practical consequence is that you cannot complete this entirely on screen. Print the page, sign it by hand, then scan or photograph the signed version and send that. It is the one step where the paper is unavoidable, and it is why so many of these still travel by fax.
Filling It In Without Getting Rejected
Your name, address, and taxpayer identification number need to match your most recent return. A mismatch, often an old address, is a common rejection reason.
Each representative needs their details and their CAF number. If they have not been assigned one yet, write "None" rather than leaving it blank. A CAF number is a unique nine-digit identifier assigned the first time someone files a third party authorization with the IRS, and a letter follows telling them what it is. After that it goes on everything.
Be precise about the tax matters and years. Vague or overbroad authorizations invite rejection, and a rejection means starting again while whatever prompted the filing carries on without help.
Fax, Online Tool, or Post
The IRS offers an online submission route for these forms, and where it works it is a reasonable option. Fax remains the fastest paper route and has one clear advantage: it produces a timestamped record you control, which matters when processing runs to weeks and you need to know exactly when something went in.
Post is the slowest of the three and gives you nothing unless you pay for certified mail with return receipt.
What Happens Next
Processing is measured in weeks rather than days, and the CAF units run backlogs at busy times of year. Faxing does not change the queue, it only removes the postal delay at the front of it. Do not resend the same authorization because nothing has appeared after a fortnight, since duplicates can create parallel entries that slow things further.
If your matter is international, meaning a foreign address, the destination is Philadelphia rather than either domestic unit, and our guide to the IRS International Accounts unit covers the wider set of routes for taxpayers abroad.
This guide explains how to submit an authorization. It is not tax or legal advice, and deciding who should represent you and on what matters is a decision worth taking seriously.
Faxing It for $1.00
1
Find your CAF unit
West of the Mississippi goes to Ogden, east goes to Memphis. Louisiana and Arkansas to Memphis, Wisconsin to Ogden, international to Philadelphia.
2
Complete the form fully
Taxpayer details matching your latest return, representative details with CAF number or "None", and the specific matters and years.
3
Sign by hand in ink
Print, sign, then scan or photograph the signed page.
4
Send at faxforadollar.com for $1.00
Up to 10 pages for a dollar, with a timestamped confirmation you can keep.
💡 Be specific about the tax matters and years you are authorizing. A form that says "all years" or leaves the matters vague invites rejection, and a rejected authorization means starting over while whatever prompted it continues without your representative able to act. List the form type, the specific years, and nothing broader than you actually intend.
Frequently Asked Questions
Where do I fax Form 2848?
To the CAF unit for your state. The IRS rule is that all states west of the Mississippi process in Ogden and all states east process in Memphis, with three exceptions: Louisiana and Arkansas go to Memphis, Wisconsin goes to Ogden, and international authorizations go to Philadelphia. Verify the current number on IRS.gov before sending.
What is the difference between Form 2848 and Form 8821?
Form 2848 authorizes someone to represent you before the IRS and act on the matters you list. Form 8821 only lets a designee inspect or receive your confidential tax information and grants no authority to act. If someone just needs to see your records, 8821 is the lighter and correct option.
Does Form 8821 go to the same fax number as Form 2848?
Yes. Both forms route to the same CAF units on the same numbers, using the same state mapping. The difference between the forms is what authority they grant, not where they are processed.
Can I sign Form 2848 electronically and fax it?
No. A faxed Form 2848 needs a handwritten signature in ink. A typed name in a PDF field or a digital signature applied in software will get the authorization rejected. Print it, sign it by hand, then scan or photograph the signed page.
What is a CAF number?
A unique nine-digit identifier assigned the first time someone files a third party authorization with the IRS. A letter follows telling them what it is, and it goes on every authorization afterwards. If your representative has not been assigned one yet, write "None" on the form rather than leaving it blank.
What is the cheapest way to fax Form 2848?
$1.00 at faxforadollar.com for up to 10 pages, with no account and no subscription. A completed 2848 is typically two pages, well inside that. A shipping store charges $3 to $5 per page for the same transmission, and there is no reason to pay a subscription for a form you send once.
Which CAF unit does my state use?
Draw a line at the Mississippi. West of it goes to Ogden, east of it goes to Memphis. Then remember three exceptions: Louisiana and Arkansas process in Memphis, Wisconsin processes in Ogden, and anything international processes in Philadelphia.
Why not just use the IRS online submission tool?
You can, and where it works it is a fine option. Fax is the fastest paper route and gives you a timestamped record you control rather than a portal receipt you cannot export. Some filers also find the online route awkward when a wet signature has to be captured anyway.
How long does the IRS take to process a faxed Form 2848?
Weeks rather than days, and longer during busy periods when the CAF units run backlogs. Faxing removes the postal delay at the front of the queue but does not change the queue itself. Do not resend after a fortnight, since duplicates can create parallel entries that slow it further.
Do I need a fax machine to send Form 2848?
No. You upload the signed pages in a browser, type the destination number, and pay. Nothing is installed and no phone line is involved. The only physical step is printing the form to sign it, which a library or workplace printer handles for pennies.
Can I authorize someone for all years and all tax matters?
You can be broad, but you should not be vague. Overbroad or unclear authorizations invite rejection, and a rejection means starting again. List the specific form types and the specific years you intend to cover, and nothing wider than you actually mean.
Who can be my representative on Form 2848?
It is limited to people qualified to represent taxpayers before the IRS, which principally means attorneys, certified public accountants, and enrolled agents, along with certain other categories. If the person helping you is not in one of those groups, Form 8821 may be what you need instead.
Why was my Form 2848 rejected?
The common causes are a typed rather than handwritten signature, taxpayer details that do not match your most recent return, a blank CAF field where "None" should have been written, and vague tax matters or years. A wrong CAF unit also causes delay, though that is misrouting rather than rejection.
What if my address changed since my last return?
Use the details that match your most recent return, since that is what the IRS matches against. If your address has genuinely changed, updating it with the IRS separately is the cleaner fix, rather than putting a new address on the authorization and hoping the match still works.
How many pages is a completed Form 2848?
Usually two. Form 8821 is typically one. Both fit comfortably in the $1.00 tier, which covers up to 10 pages. If you are submitting several authorizations at once, count the total before sending, since pricing moves to $1.99 for 11 to 25 pages.
Is it safe to fax a form with my Social Security number?
A fax travels point to point to the number dialled rather than sitting on a mail server, which is a large part of why the IRS accepts these by fax. Check the destination twice, since transposing a digit is the genuine risk. On this service the uploaded file is deleted from the servers once the fax has been sent.
Does the IRS confirm they received the authorization?
Not by acknowledgement. Your evidence is the transmission confirmation, which records the destination number, the page count, and the exact date and time. Since processing takes weeks, that record is what tells you whether enough time has genuinely passed to chase it.
Can my accountant fax the form for me?
Yes, and representatives commonly submit these themselves. What matters is that your signature on the form is handwritten and that the taxpayer details match your return. Who presses send is irrelevant to whether the authorization is valid.
What if I live abroad?
International authorizations process in Philadelphia rather than either domestic unit. That applies based on the taxpayer having a foreign address. Our guide to the IRS International Accounts unit covers the wider set of routes for taxpayers outside the United States.
Can I revoke a Form 2848 later?
Yes, authorizations can be revoked, and the process for doing so is set out in the form instructions. It is worth knowing before you file one, particularly if you are authorizing a firm rather than an individual, since the authorization does not simply lapse because you stopped working with them.
Should I fax and also post the same authorization?
Pick one. Duplicate submissions can create duplicate CAF entries, which causes confusion rather than speed. Fax arrives in minutes rather than days, so if you are choosing between them, choose fax and keep the confirmation.
Is there any benefit to sending outside office hours?
Only a small one, but it is free. The equipment receives continuously and your confirmation records that timestamp, with a human picking it up the next business day. Since CAF processing runs to weeks anyway, the gain is marginal, but it costs nothing to send on Friday evening rather than Monday morning.
What if my fax to the CAF unit fails?
CAF fax lines are busy, particularly around filing deadlines, and a busy signal usually reflects volume rather than a wrong number. A failed send is refunded automatically here, so nothing is lost. Wait an hour and retry, and re-check the state mapping before assuming the number is wrong.
Will my handwritten signature transmit clearly enough?
That is a real concern here, because the signature is the thing that makes the authorization valid. Fax transmits in pure black and white with no grey, so a faint ballpoint signature photographed in poor light can arrive too weak to accept. Sign in dark ink, press firmly, and scan rather than photograph if you can. PDF, Word, JPG and PNG are all accepted.
Do I need a separate form for each representative?
One Form 2848 can list multiple representatives, each with their own details and CAF number. What you should not do is leave any of them incompletely identified, since a partially completed representative section is a rejection risk for the whole form.
Does an authorization expire?
Form 8821 authorizations have a defined expiry behaviour, and Form 2848 authorizations remain until revoked or superseded, subject to the terms on the form. Read the instructions on the current version rather than relying on what was true several years ago, since the IRS has revised these rules.
Is my authorization stored anywhere after sending?
No. The file is deleted from the servers once the transmission completes. You keep your own copy and the confirmation email, and both are worth holding until the authorization actually shows as active, since that is the window in which you might need to prove when it was submitted.
Can I use Form 8821 for a mortgage lender?
That is one of its common uses, since a lender verifying income needs to see tax information but has no business representing you. Form 8821 grants exactly that and nothing more, which is why it is the appropriate choice rather than a power of attorney.
Is this page tax or legal advice?
No. It explains how to get an authorization to the right CAF unit and what commonly causes rejections. Deciding who should represent you before the IRS, and on which matters and years, is a decision with real consequences and worth discussing with the professional you are appointing.
Form signed by hand and CAF unit identified?
Send it to the right CAF unit for $1.00 and keep the timestamped confirmation while it works through processing.
Send a Fax, $1