How long does EIN application take? Online vs fax vs mail?

Just formed my Delaware LLC. Need an EIN to open a bank account. Seeing different options on IRS website — online, fax, mail. Which is fastest? Any gotchas?

Online is instant — you get EIN immediately. But it only works if you have a US SSN or ITIN. Hours are M-F 7am-10pm EST.

Fax takes about 4 business days. Mail takes 4-6 weeks. No reason to use anything but online if you qualify.

If you're a foreign founder without SSN, you need to fax Form SS-4. I used a service that faxed it for me and got EIN in 5 days. Some people report calling the IRS directly works too but expect long hold times.

I have SSN. Just did it online — literally took 5 minutes. Got the EIN confirmation letter PDF immediately. That was way easier than expected.

Pro tip: some banks want you to wait 24-48 hours after getting EIN before opening account. The EIN needs to "propagate" through IRS systems. Had a bank reject my application because they couldn't verify the EIN same-day.

Just got my EIN today — took literally 10 minutes from start to finish. Used the IRS online application at irs.gov/ein. Answered 5-6 questions about my LLC, confirmed my SSN, and boom — instant approval with a PDF confirmation letter.

The system is only available M-F 7am-10pm Eastern. I made the mistake of trying on a Sunday first — just says "service unavailable."

If you're a US person with an SSN, there's zero reason to use mail or fax. It's genuinely the smoothest IRS experience I've ever had.

International founder here (UK citizen, no SSN or ITIN). The online system doesn't work for us — you get blocked at the SSN/ITIN screen.

Here's what actually worked: Downloaded Form SS-4 from IRS website, filled it out completely (make sure to check "Foreign" for third party designee if using a service), and faxed to the IRS international fax line: 855-215-1627.

Took exactly 11 business days to receive my EIN via fax back. Some people report calling the IRS directly at the international line (267-941-1099) but I couldn't get through after 2+ hours on hold.

Key tip: Use your foreign passport number in the "identifying number" field if you don't have an ITIN. Works fine.

Warning: my application got rejected and I almost panicked. Here's what happened and how I fixed it.

I entered my LLC name as "Smith Consulting" but my Delaware formation docs had it as "Smith Consulting LLC" (with the LLC suffix). The IRS system kicked back an error saying "entity name doesn't match records."

Fix was simple: I had to enter the EXACT legal name including "LLC" at the end. Resubmitted and got approved instantly.

Other common rejection reasons I learned about: (1) applying too soon after formation — sometimes state records take 24-48 hours to sync, (2) using a PO Box when the form wants a physical address, (3) trying to get a second EIN when you already have one for that entity.

Also useful: if you're just starting your LLC, check out the Delaware LLC formation guide — covers the full process from formation to EIN to bank account.