taxID

taxID · Recommended

Appears in

Organization

What is it?

A tax ID is a government-issued number that identifies an organization or individual for tax purposes. Every country has its own name and format for this number: the EIN (Employer Identification Number) in the United States, the CIF or NIF in Spain, the SIRET in France, the ABN in Australia. Schema.org's taxID property provides a single field for publishing this identifier in structured data, regardless of jurisdiction.

Why this matters for AEO

Tax IDs are some of the strongest entity disambiguation signals available because they are issued by governments and tied to legal registrations. When an AI answer engine sees a tax ID in structured data, it can cross-reference the identifier against known records to confirm that the entity is a real, registered business. This is particularly important for organizations with common names, organizations that operate under multiple trade names, or organizations that have changed names. Google explicitly recommends taxID in its Organization structured data guidelines, signaling that it factors into knowledge graph confidence.

What the specs say

Schema.org:taxID expects a Text value. The Tax / Fiscal ID of the organization or person, e.g. the TIN in the US or the CIF/NIF in Spain. [Source: https://schema.org/taxID]

Google: Recommended. "The tax ID associated with your Organization." [Source: https://developers.google.com/search/docs/appearance/structured-data/organization]

How to find your value

The process varies by country:

• United States: Your EIN (Employer Identification Number) is assigned by the IRS and appears on your CP 575 notice, Form 941, or W-2 forms. Format: XX-XXXXXXX.
• United Kingdom: HMRC issues a Unique Taxpayer Reference (UTR), a 10-digit number found on tax returns and correspondence.
• Spain: The CIF (Certificado de Identificación Fiscal) for companies or NIF for individuals is found on the tax authority's certificate. Format: a letter followed by 8 characters (e.g., B12345678).
• France: The SIREN (9 digits) or SIRET (14 digits) is issued by INSEE and found on Kbis extracts.
• Australia: The ABN (Australian Business Number) is 11 digits, found at https://abr.business.gov.au/.
• Germany: The Steueridentifikationsnummer is 11 digits for individuals; companies receive a Steuernummer assigned by state tax offices.

Format and code

taxID is a plain text string. Use the format native to your jurisdiction, including any standard separators or prefixes:

{
  "@context": "https://schema.org",
  "@type": "Organization",
  "name": "Apple Inc.",
  "taxID": "94-2404110"
}

For a Spanish company:

{
  "@context": "https://schema.org",
  "@type": "Organization",
  "name": "Banco Santander SA",
  "taxID": "A39000013"
}

Avoid including labels or prefixes that are not part of the actual identifier:

{
  "taxID": "EIN: 94-2404110"
}

That format above is invalid. Use only the identifier itself.

Webflow implementation

Static pages

Add the JSON-LD block to your homepage or About page via Page Settings > Custom Code > Head Code:

<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "Organization",
  "name": "Your Company",
  "taxID": "XX-XXXXXXX"
}
</script>

CMS template pages

taxID is an organization-level field, not a per-page or per-item field. Set it once in a site-wide organization schema on your homepage or company About page rather than binding it to CMS fields.

In Schema HQ

taxID is output in the Organization schema editor under the Disambiguation section. Enter your tax ID once and it is published automatically with every organization schema block on your site.

Real examples

Apple Inc.'s EIN (94-2404110) is publicly documented in SEC filings. Banco Santander's CIF (A39000013) appears on official Spanish company registries. These are real identifiers tied to real legal entities, which is precisely what structured data consumers look for.

{
  "@context": "https://schema.org",
  "@type": "Organization",
  "name": "Stripe, Inc.",
  "url": "https://stripe.com",
  "taxID": "45-4166877"
}

Related fields

• vatID
• leiCode
• duns
• iso6523Code
• companyRegistration

FAQ

Should taxID include the country prefix or not?

Follow the standard format for your country. In the US, EINs are written as XX-XXXXXXX. In Spain, CIFs include the letter prefix. Do not prepend a country code unless that country code is genuinely part of the official identifier format. For cross-border identifiers with mandatory country prefixes, consider using vatID or iso6523Code instead.

Is it safe to publish a tax ID publicly?

In most jurisdictions, business tax identifiers are semi-public. They appear in company filings, SEC documents, and business registries. For individuals, tax IDs (like personal SSNs) should never be published. This field is appropriate for organizations, not persons, in almost all practical implementations.

What if the organization operates in multiple countries?

Use the primary tax ID for the legal entity whose website this is. If the organization has multiple legal entities in different jurisdictions, choose the one that corresponds to the registered organization behind the site. Additional identifiers can be expressed using iso6523Code with jurisdiction-specific prefixes.