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US EIN Validator

Check whether an Employer Identification Number (EIN) is well formed and uses an IRS-assigned prefix.

How it works

An EIN is made up of 9 digits in the XX-XXXXXXX format. The tool validates the format and checks that the first two digits are not in the IRS list of unassigned prefixes. The hyphen is optional: 123456789 and 12-3456789 are treated the same way.

Facts about the EIN Validator

  • An EIN has exactly 9 digits in the XX-XXXXXXX format.
  • The first two digits indicate the IRS campus that assigned the number.
  • Some prefixes (such as 07, 08 and 09) are not assigned by the IRS.
  • Validation only checks format and prefix, without consulting any database.

Official references

See the official IRS pages to understand how EINs work:

Frequently Asked Questions

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