How long does the IRS take to fax back my EIN?

The IRS target and what we actually measure

Two numbers get confused here, so both belong in one place.

The IRS's own published target under the Fax-TIN program is 4 business days. That is what the IRS aims for, and it is what most guides quote.

What we measure is slower. Across the EIN fax-backs that have arrived at FaxTerra numbers, about 17 days is typical, 87 percent have arrived by day 21, and the slowest we have recorded took 72 days. Replies do not trickle in evenly: most land in a burst during weeks two and three, then almost stop.

So if it has been a few days and nothing has come, nothing is wrong. The full distribution, with its sample size and method, is on our measured IRS response-time page.

Day 21 is when to stop waiting and call

This is the part the raw averages hide. Once 87 percent of replies have already arrived, the question stops being "how long is the average" and becomes "given nothing has come by now, will anything come at all". Of the applications still waiting at three weeks, only about one in four ever receives a fax. Waiting another week barely moves that.

So at three weeks, call. It is the reliable way to get your EIN from that point, and it works long after the fax-back window has passed.

Calling the IRS about a pending SS-4

Inside the United States, call the IRS Business and Specialty Tax Line on (800) 829-4933, Monday to Friday, 7am to 7pm local time. From outside the United States, call (267) 941-1099. That international line is not toll free, and its hours are set in Eastern Time, so check the difference before you dial.

Have these ready before you call, because the agent will ask for them: the legal name of the entity exactly as you wrote it on the form, its mailing address, the name and taxpayer identification number of the responsible party from line 7, the date you faxed the form, and the fax number you want the reply sent to.

Keep your fax number active for the call itself. The agent can fax a Letter 147C, the official EIN verification, back to you while you are on the line, so you need a working fax line to receive it.

Which IRS faxes get a reply at all

Only the EIN application does. Form SS-4 goes to one of three published IRS fax lines, chosen by where your business is based, and the IRS faxes a notice carrying your assigned EIN back to the fax number on the form.

The EIN application is the only IRS destination in our own directory marked as one that faxes a reply back, and it is the only one we have ever recorded a fax-back arriving from. That is why we only offer to watch for a reply on SS-4 sends. We are describing what we can see, not making a claim about how the IRS handles every other form.

One field decides whether any of it reaches you: "Applicant's fax number", in the signature block at the bottom of the form. That is the box the IRS reads. If it is empty, the IRS does not say how or when your EIN would arrive.

What the SS-4 Assistant does, and what it does not

When you fax one of the SS-4 lines from FaxTerra, the composer offers to check in on the reply. One tap arms it and it asks you for nothing.

What it does: your inbox already catches the reply and notifies you when any fax arrives, and a fax from a line the IRS is known to send EIN assignments from is labeled "Likely from the IRS". The check-in adds the timing: if nothing has arrived from an IRS line by day 21, we send you one email saying it is time to call instead, with the script above. That is the only email it sends.

What it does not do: it does not fill in your form, choose your entity type, advise you, act as your third party designee, or call the IRS for you. It does not read your document. You fill in your own SS-4, sign it and send it; we tell you when it has been long enough.

It needs a receiving number to work, because that is where the reply lands. FaxTerra is not affiliated with the IRS, and none of this is tax or legal advice; the IRS instructions are the authority.

What we store about your application

We store no answers, because we never ask for any. Arming the watch asks you nothing at all.

What we keep is a handful of workflow facts your account already produced by sending a fax: which published IRS line you faxed, whether your account held a receiving number at that moment, whether a fax later arrived from a known IRS line, and how it ended. No names, no addresses, no Social Security or taxpayer identification numbers, no dates of birth. There is nothing sensitive in it to protect, which is exactly why we built it this way.