If you’re setting up a business in or with the US, you’ve probably run into both terms, DUNS number and Tax ID, sometimes on the same form. It’s a fair question to ask whether they’re the same thing. They’re not. A DUNS number and a Tax ID (usually referring to an EIN in the US context) come from two completely different systems, serve different purposes, and one doesn’t substitute for the other.
We cover this as part of a broader three-way comparison in our guide, DUNS Number vs EIN vs Tax ID: What’s the Difference — this post focuses specifically on how DUNS compares to a US Tax ID.
What “Tax ID” Usually Means in the US
“Tax ID” is a general term, and in the US it most commonly refers to an EIN (Employer Identification Number), issued by the IRS. It’s used to identify your business for federal tax purposes — filing returns, handling payroll, and opening a business bank account. Occasionally, “Tax ID” can also refer to a Social Security Number for sole proprietors without an EIN, but for most registered businesses, Tax ID and EIN are used interchangeably.
What a DUNS Number Is, By Comparison
A DUNS number is issued by Dun & Bradstreet, a private company — not a government tax authority. It doesn’t relate to your taxes at all. Instead, it identifies your business within D&B’s global business database, which platforms, suppliers, and government systems use to confirm your business is legitimate and to check your business credit profile if needed.
Side-by-Side Comparison
| DUNS Number | Tax ID (EIN) | |
| Issued by | Dun & Bradstreet (private company) | IRS (US government) |
| Purpose | Business identity and credit verification | Federal tax reporting |
| Required for | Government contracts, global platform verification, supplier credit checks | Filing taxes, payroll, opening a US business bank account |
| Format | 9-digit number | 9-digit number (formatted as XX-XXXXXXX) |
| Cost | Free | Free, applied for directly through the IRS |
| Geographic scope | Global | US only |
Notice that both happen to be nine digits, which is part of why people sometimes assume they’re the same kind of number. They’re not connected in format, purpose, or issuing authority.
When You Need a DUNS Number in the US Context
- To register for your contract eligibility, including for federal government contracting, a DUNS number (or current equivalent) is generally a requirement other than your Tax ID.
- Platform business verification: Apple Developer, Google Play, Microsoft Partner Centre and other platforms may need a DUNS number to verify that your business is real, irrespective of how you are taxed.
- B2B credit relationships: suppliers or partners checking your business’s credit history through D&B’s database rely on your DUNS number, not your Tax ID.
When Your Tax ID Is All You Need
- Standard federal and state tax filing.
- Compliant Payroll Processing for US workers
- Setting up a US business account in the States
- For most small business loans, lenders will require your EIN, rather than a DUNS number.
Can You Have Both, and Do They Interact?
Yes, and for many old-time American businesses, both exist totally differently on your paperwork. Your EIN doesn’t transfer over to your DUNS application, and D&B doesn’t report anything back to the IRS. If a form is requesting two forms of proof, it is because it actually requires both, not because it’s asking for proof twice.
What If You’re a Non-US Business Comparing the Two?
Generally speaking, it’s easier to decide whether you need a Tax ID (EIN) or a DUNS number if you’re outside the US and deciding whether you need one or the other: You probably need a DUNS number if a global platform or supplier requires business verification; you probably do not need a US EIN unless you have specific tax obligations in the US (e.g., you sell into the US in a manner that triggers the filing of US taxes). For most international applicants, the tax identifier used is from their own country, rather than a US Tax ID (PAN or GST in India, for example). We cover this in more detail in our guide, DUNS Number Without an EIN.
A Quick Way to Check Which One You Actually Need
Look at exactly what’s being requested:
- If the form is about taxes, payroll, or US banking: that’s your Tax ID (EIN)
- If the form is about business verification, contract eligibility, or platform onboarding: that’s almost certainly your DUNS number
- If a form genuinely lists both as separate fields: provide whichever applies, and don’t assume one can substitute for the other
Is a DUNS number the same as a Tax ID in the USA?
No. A DUNS number is issued by Dun & Bradstreet for business verification. A Tax ID (typically an EIN) is issued by the IRS for tax purposes. They’re unrelated systems.
Do I need both a DUNS number and a Tax ID for my US business?
It depends on what you’re doing. Standard tax filing only needs your Tax ID. Government contracting or platform verification typically also requires a DUNS number.
Can I use my EIN instead of a DUNS number on a form that asks for one?
No, if a form specifically asks for a DUNS number, your EIN won’t be accepted in that field, since they’re different identifiers entirely.
Does getting an EIN automatically generate a DUNS number for my business?
No. There’s no connection between the IRS and D&B’s systems. You’d need to apply for a DUNS number separately if you need one.
Is a DUNS number only relevant for US businesses?
No, it’s a global identifier. Businesses in India, the UK, and elsewhere apply for DUNS numbers too, independent of any US Tax ID.