DUNS Number vs EIN: Key Differences Explained

When you start a business, you'll quickly encounter two important identification numbers: the EIN and the DUNS number. Both are 9-digit identifiers, both are essential for running a legitimate US business — and both are completely different from each other. This guide explains exactly what each one is, who issues it, what it's used for, and when you need both.

Quick Comparison: DUNS Number vs EIN

What Is an EIN?

An EIN (Employer Identification Number) is a 9-digit number issued by the Internal Revenue Service (IRS). It is the US federal government's way of identifying your business for tax purposes — functioning much like a Social Security Number (SSN) does for individuals.

EINs are formatted as two digits, a hyphen, and then seven digits: XX-XXXXXXX. For example: 12-3456789.

What Is an EIN Used For?

Who Needs an EIN?

Any US business that has employees, operates as a corporation or partnership, files certain tax returns, or withholds taxes on income paid to non-resident aliens is required to have an EIN. Even sole proprietors without employees often choose to get one to avoid using their Social Security Number for business purposes.

Getting an EIN is free and can be done instantly online through the IRS website. The IRS issues your EIN immediately upon completing their online application — no waiting period required.

What Is a DUNS Number?

A DUNS number (Data Universal Numbering System) is a 9-digit identifier issued by Dun & Bradstreet (D&B), a private commercial data company. Unlike the EIN, the DUNS number is not issued by a government agency — it is a commercial standard that has become the global default for business identification.

DUNS numbers are formatted as three groups of three digits separated by hyphens: XXX-XXX-XXX. For example: 123-456-789. The number is permanent and stays with your business even if you move locations or change your name.

Introduced in 1962, the DUNS system now covers over 455 million businesses in 224 countries — making it the world's most widely adopted business identifier outside of government tax systems.

What Is a DUNS Number Used For?

Key Differences Between DUNS and EIN

1. Who Issues Them

The EIN is issued by the US government (IRS). It is a legal requirement for most US businesses and is tied to your tax obligations as defined by federal law.

The DUNS number is issued by Dun & Bradstreet, a private company. There is no legal mandate to have a DUNS number — but it has become a de facto requirement for many business activities, both public (government contracts) and private (Apple, Google, enterprise B2B).

2. What They Are Used For

EIN = tax identity. Your EIN is used by the IRS to track your business's tax obligations. It tells the government who you are for the purposes of federal taxation.

DUNS = commercial identity. Your DUNS number is used by businesses, governments, and platforms to verify that your company exists, is legitimate, and can be looked up in a global database of 455 million businesses.

3. Geographic Scope

An EIN is a US-only identifier. It is issued by the IRS and is only relevant within the United States tax system. Foreign companies doing business in the US may need an EIN for tax purposes, but it has no relevance outside the US context.

A DUNS number is global. Businesses in 224 countries use DUNS numbers, and the system is recognized by international organizations including the United Nations, NATO, and the European Commission.

4. Privacy and Public Access

Your EIN is relatively private — it should only be shared with the IRS, financial institutions, and trusted vendors on W-9 forms. Sharing your EIN publicly can expose you to identity theft risks.

Your DUNS number, by contrast, is a public identifier. It can be looked up by anyone in the D&B database. This transparency is by design — it allows counterparts to verify your business exists before entering into transactions.

When You Need Both

Most serious US businesses need both an EIN and a DUNS number. Here are the key scenarios where both are required simultaneously:

DUNS Number for Business Credit Building

One of the most important — and most overlooked — uses of a DUNS number is establishing your business credit profile. When you have a DUNS number and start making purchases on net-30 payment terms with vendors who report to D&B, you build a Paydex score.

The Paydex score is D&B's business credit score, ranging from 0 to 100. A score of 80 or above indicates that you consistently pay on time. This score is separate from your personal credit score and can be used to qualify for business credit cards, lines of credit, and loans without putting your personal credit at risk.

Without a DUNS number, you have no D&B credit file. This means lenders and suppliers have no independent way to verify your payment history, which can make it harder and more expensive to access business credit.

EIN for Tax and Banking

The EIN is the foundational identifier for your US business from a legal and banking perspective. You cannot open a business bank account, process payroll, or file business taxes without one. For LLCs, corporations, and partnerships, an EIN is mandatory from day one.

For sole proprietors with no employees, an EIN is optional — you could use your SSN instead — but most financial advisors recommend getting one to keep business and personal finances cleanly separated and to reduce identity theft risk.

How to Get Each One

Frequently Asked Questions