Lost Your EIN? How to Find It Again (2026)

Your EIN has not been cancelled, revoked, or lost by the IRS. Once assigned, an EIN belongs to your entity permanently — it is never reissued to anyone else and never expires. You have simply misplaced the piece of paper with the number on it.

That is a recoverable situation, usually in one phone call. Here is where to look first, and the one shortcut you must not take.

Do not apply for a new EIN. It is the intuitive move and it is the wrong one. A second Form SS-4 for the same LLC creates a duplicate EIN, splitting your filings, bank records, and processor accounts across two numbers for one entity. Cleaning that up takes IRS correspondence. Recovering the original takes a phone call.

Step 1: Check These Six Places First

Before calling the IRS, spend ten minutes here. Most owners find it in one of these:

Where	What to look for
Your CP 575 notice	The original EIN assignment letter from the IRS. Search your email for “CP 575,” “EIN,” or the IRS fax number if it was faxed to you.
Formation company dashboard	If a service formed the LLC and obtained the EIN, it is almost certainly in your account or the onboarding email thread.
Business bank account documents	Mercury, Relay, Wise, and traditional banks all captured the EIN at onboarding. Check the account application or your account profile.
Prior tax filings	Any previously filed Form 5472 and pro forma 1120, or a Form 7004 extension, carries the EIN on the header.
Payment processor settings	Stripe, PayPal, and Amazon tax-information settings store the EIN you entered at signup.
Your accountant or preparer	Anyone who has prepared or reviewed a filing for the LLC has it on record.

What will not work:searching the IRS website. There is no public EIN lookup for private businesses — the IRS treats an EIN as confidential taxpayer information. Third-party “EIN lookup” sites mostly index public companies and nonprofits, whose EINs are disclosed in public filings. A privately held foreign-owned LLC will not be there.

Step 2: Request Letter 147C From the IRS

If none of the above turns it up, the IRS will tell you your own EIN over the phone and send written confirmation. The document is Letter 147C, and it is free.

From outside the US: call 267-941-1099 (not toll-free), Monday to Friday, 6:00 a.m. to 11:00 p.m. Eastern.
From inside the US:call the Business & Specialty Tax line at 1-800-829-4933, Monday to Friday, 7:00 a.m. to 7:00 p.m. local time.
Choose fax delivery. It arrives in minutes, often before you hang up. Mail takes four to six weeks.

You will need to pass identity verification — the exact legal entity name, the address on file, your role in the business, and the formation state. The full walkthrough, including what to do if verification fails, is in our Letter 147C guide.

Got your EIN back? Form5472.ioturns it into a complete, IRS-ready Form 5472 + pro forma 1120 in about 15 minutes — from $147, no CPA required.

Start your filing →

If a Filing Deadline Is Close

A lost EIN is not a recognised reasonable-cause excuse for filing Form 5472 late, and the $25,000 penalty does not pause while you look for paperwork. Priorities in order:

Call the same day and take fax delivery of the 147C. This can resolve the whole problem within an hour.
File Form 7004 for an extensionif the deadline is genuinely imminent — note that the extension form also requires the EIN, so recovering the number still comes first. See the Form 7004 guide.
Do not reapply to get a number quickly. A duplicate EIN turns a one-hour problem into a multi-month one.

Storing It So This Does Not Happen Again

Save the CP 575 or 147C PDF somewhere permanent — not only in an email inbox you might lose access to.
Keep it with your Form 5472 supporting records, which you need to retain anyway.
Make sure the IRS has an address you actually control. If it does not, file Form 8822-B — otherwise every future IRS letter, including penalty notices, goes somewhere you cannot read it.

Key Takeaways

Your EIN is permanent— it is misplaced, not lost.
Check bank documents, formation-service accounts, prior filings, and processor settings before calling.
There is no IRS online EIN lookup for private businesses.
Call 267-941-1099 from abroad, request Letter 147C, and take fax delivery.
Never reapply— a duplicate EIN is a much bigger problem than a missing letter.

Frequently Asked Questions

Can I look up my EIN online?

Not through the IRS.There is no public EIN lookup for private businesses — the IRS treats an EIN as confidential taxpayer information and will only release it to an authorized person over the phone. Third-party sites claiming to search EINs generally only cover public companies and nonprofits, which file their EINs publicly.

What if my formation company applied for the EIN and never gave it to me?

Ask them first— most keep it in your account dashboard or the original onboarding email. If they are unresponsive or no longer in business, request Letter 147C from the IRS directly. Be aware that if they listed one of their own staff as the responsible party, you may fail IRS identity verification, in which case you also need to file Form 8822-B to correct the record.

Should I just apply for a new EIN if I cannot find the old one?

No. This is the costliest mistake in this situation. Filing a second Form SS-4 for the same LLC creates a duplicate EIN, and now two numbers exist for one entity. Your filings, bank records, and payment processors end up split across both, and untangling it requires IRS correspondence. Recover the existing EIN instead.

How quickly can I get my EIN back before a filing deadline?

Often within the same call, if you phone the IRS and choose fax delivery of Letter 147C. That is why the phone route matters when a Form 5472 deadline is close — mail delivery takes four to six weeks and will not save a deadline.

Does losing my EIN letter affect my Form 5472 obligation?

No. Your filing obligation and its deadline are unchanged by whether you can find your paperwork, and a lost EIN is not a recognized reasonable-cause excuse for filing late. Recover the number and file on time.