Brand & Design

What is an EIN?

Employer Identification Number, a nine-digit federal tax ID assigned by the IRS to businesses, nonprofits, and other entities operating in the United States.

Also known as: Employer Identification Number, Federal Tax ID, FEIN

An EIN is the business equivalent of a social security number, formatted as XX-XXXXXXX. The IRS issues one per legal entity at formation; you use it on tax filings, bank account openings, payroll registrations, and most B2B onboarding flows that need to verify a counterparty is a real US business.

EINs are not strictly secret (they appear on W-9 forms and many public filings) but they are also not freely searchable. Public databases exist for nonprofits (the IRS publishes 990 filings) and SEC-registered entities, but for private companies the EIN is something the company has to disclose in a contract or onboarding flow.

For brand-data and KYC use cases, the EIN is the canonical key for tying a website to a legal entity. Combined with NAICS or SIC for industry classification and a verified address, it is the minimum bar for "is this business real and who is it." Brand.dev pulls EINs (where available) as part of company-data enrichment alongside DUNS numbers and ticker symbols.

In the wild

  • A SaaS onboarding form asking for company name and EIN to provision a paid account
  • A KYC pipeline matching the EIN on a W-9 to the EIN in IRS filings before approving an ACH transfer
  • A business-data API returning EIN, NAICS, and address when given a domain

How Brand.dev uses ein

Endpoints in the Brand.dev API where this concept comes up directly.

FAQ

EIN vs DUNS number?

EIN is a US tax ID issued by the IRS. DUNS is a global business identifier issued by Dun & Bradstreet. A US company typically has both; an international supplier may have only a DUNS.

Is an EIN public?

For nonprofits and public companies, yes (via 990 filings and SEC documents). For private companies, the EIN is shared selectively; it is not in a public IRS lookup.

Do sole proprietors have EINs?

They can request one but are not required to: a sole prop can use the owner's SSN. EINs become mandatory once the business has employees, runs payroll, or is taxed as a corporation or partnership.

Related terms

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