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EIN Format Validator
Paste an EIN and we'll check the format, tell you what each digit means, and flag common vendor-application mistakes.
9 digits, format XX-XXXXXXX. We don't send this anywhere or store it.
What each digit means
XX-XXXXXXX
First 2 digits = prefix / campus code. Identifies which IRS office issued the EIN. All EINs starting with 20, 26, 27, 45, 46 through 88 were issued online (fastest path).
XX-XXXXXXX
Last 7 digits = sequential serial. No meaning individually; the IRS assigns them in order per campus.
Common mistakes on vendor applications
- Typing SSN instead of EIN — SSN is 3-2-4 digits (XXX-XX-XXXX), EIN is 2-7 (XX-XXXXXXX).
- Entering formatted with spaces or dots — most vendor forms accept only digits or standard dash format.
- Confusing the EIN with a state tax ID — those are separate numbers issued by your state, not the IRS.
- Reversing prefix and serial — always the shorter group (2 digits) comes first.
Continue in Sterling
Don't have an EIN yet?
Sterling's guided EIN wizard walks you through every field on IRS Form SS-4, prefilled from your business info. Get an EIN online in ~10 minutes instead of guessing at IRS wording.