An EIN confirmation letter is an IRS document confirming the Employer Identification Number assigned to a business. The two versions KYB teams see most are the CP 575 notice, issued when the EIN is assigned, and Letter 147C, "EIN Previously Assigned," which confirms an existing EIN. The IRS now also provides a digital CP 575 through Business Tax Account, which it says "can be used as a substitute for the original CP575A-J notice series and Letter 147C" and "is accepted by banks and other institutions as written confirmation of an entity's EIN" (IRS).
Why it matters in KYB review
For a US business, the tax identification number is a required CIP data point (31 CFR 1020.220). The EIN letter ties that number to the exact legal name the IRS has on file. A mismatch between the name on the letter and the name on the formation documents is an informative exception: it can mean a name change that was never reported, a typo, a different entity with a similar name, or a borrowed EIN.
EIN letters are also short documents with a predictable layout, which makes them easy to imitate. Treat a PDF as a claim until something independent confirms it.
What an analyst checks
- Name match. The legal name on the letter matches the articles, the registry and the application exactly, including punctuation and suffix.
- EIN match. Same number on the letter, the application and any tax documents.
- Letter type and date. A CP 575 dated before the company's formation date needs an explanation. A 147C dated years after formation is normal.
- Address. The IRS mailing address is often the owner's or an accountant's address; that alone is not a red flag, and it should still be explainable.
- Visual integrity. Fonts, alignment, notice codes and edits that betray a template. Compare with genuine examples your team has seen.
- Independent corroboration. Where your program has a TIN-matching or data-provider check, confirm the name and EIN combination there too.
Common pitfalls
- Accepting a screenshot of an online form. The EIN application confirmation page is not the CP 575 notice.
- Ignoring small name differences. "Kestrel Freight LLC" on the letter and "Kestrel Freight Ltd" on the application are different entities until explained. (Illustrative example.)
- Treating the letter as proof of good standing. It says nothing about state status. See certificate of good standing.
- Waiting on the wrong party. These letters are addressed to the business, so the applicant has to supply them. Ask once, in a consolidated RFI.
Related terms
Business verification documents, articles of incorporation / organization, request for information (RFI), KYB (Know Your Business).
How Sweat AI fits
Sweat AI's KYB reviews reconcile the legal name and EIN across every document in the file and list each mismatch with the documents involved. See KYB review.
Questions
What is the difference between CP 575 and Letter 147C?
The CP 575 is the notice issued when an EIN is assigned. Letter 147C, "EIN Previously Assigned," confirms an EIN that already exists. The IRS also offers a digital CP 575 through Business Tax Account and describes it as accepted by banks as written confirmation of an EIN.
Does an EIN letter prove the business is operating?
No. It shows that the IRS assigned a number to that name. It does not show activity, ownership or good standing.
Sources
- IRS, Understanding your CP575 notice, accessed 2026-09-30
- 31 CFR 1020.220, Customer identification program requirements for banks (eCFR), accessed 2026-09-30