Check an EIN Format
How EINs Are Structured
An EIN always follows the format XX-XXXXXXX: two digits, a hyphen, then seven digits. The first two digits are the IRS campus prefix — they identify the service center that assigned the number (for example, prefixes 04 and 10 point to the Philadelphia campus). The remaining seven digits are a serial number with no hidden meaning. A number that breaks this format, contains letters, or has extra digits is invalid on its face.
What the IRS Will and Will Not Confirm
The most important fact about EIN verification: the IRS does not publicly confirm an EIN's owner, and it will not verify a number over the phone or by email to third parties. Any service that claims to give you a "live IRS match" for an arbitrary company name is not doing what it says. The legitimate paths to confirming an EIN are:
- W-9 form — the counterparty attests its own EIN under penalty of perjury. This is the single most practical verification document in commercial use.
- 147C letter — the IRS's official confirmation of an EIN, issued to the taxpayer. Request it from the company if you need documentary proof.
- CP575 notice — the original EIN assignment notice, held by the business.
- Tax transcripts — obtainable only with the business's authorization.
Cross-Checks That Catch Fake EINs
Because the IRS channel is closed to third parties, real-world EIN verification combines the documents above with public-record cross-checks:
- State registry match — the entity name on the W-9 should match the state incorporation record. If the company claims to be a Delaware corporation and no Delaware filing exists, the paperwork is suspect.
- Format and campus sanity — the campus prefix should be a known IRS prefix; a number like 00-0000000 or one using an unused prefix range is a fabrication tell.
- Consistency across documents — the EIN on the invoice, the W-9, and the bank details should all match; discrepancies are the classic vendor-fraud pattern.
- Freshness — a newly assigned EIN for a company that claims years of trading history is worth a question.
Red Flags When a Vendor Gives You an EIN
- The EIN appears on the invoice but the vendor refuses to provide a W-9.
- The name on the W-9 does not match the state registry or the name on the invoice.
- The EIN's campus prefix does not exist in the IRS prefix table.
- The company claims to be registered in a state where its registry returns no record.
For a complete picture, pair the EIN documents with an HQ Trust Score report, which layers sanctions screening and litigation history over the registry and tax-ID checks.