EIN lookup for business owners: Where to find or retrieve your tax ID

If you’re starting or running a business, your Employer Identification Number (EIN) is one of the first pieces of information you’ll need. It shows up on tax forms, loan applications, bank accounts, payroll systems—nearly every official part of your financial infrastructure.

But whether you're just getting set up or revisiting old documents, it’s easy to misplace your EIN or forget where it’s stored. 

This guide walks through how to find your EIN (or your employer’s), what to do if you’ve lost it, and how much of this information is publicly accessible online.

What is an EIN and why it matters

An Employer Identification Number (EIN) is a unique nine-digit number issued by the IRS to identify a business for tax and administrative purposes. Think of it like a Social Security Number (SSN)—but for your business.

You’ll use your EIN to:

• File business taxes
• Open a business bank account
• Apply for licenses and permits
• Run payroll or issue W-2s to employees
• Secure financing or credit under your business name

The IRS provides your EIN after you file Form SS-4—typically delivered in a confirmation letter (CP 575). From there, it becomes part of your business’s core documentation. 

So if you plan to open a business account, such as with Rho, you’ll need your EIN ready. It’s one of the first steps in setting up your company’s financial infrastructure—and something we help you build on from day one.

How to find your EIN as a business owner

If you’ve already registered your business and been assigned an EIN, but can’t remember where it’s stored—that’s common. 

The good news is, the IRS includes your EIN in several official documents and systems you likely already use.

Ways to locate your EIN:

• IRS confirmation letter (CP 575): This is the original document issued by the IRS when your EIN was approved. If you saved a PDF or printed version, this is the most reliable source.
• Business tax returns: Your EIN appears at the top of any tax return you’ve filed under your business name (e.g., Form 1120, 1065, or Schedule C).
• Banking documents: If you’ve opened a business bank account, your EIN was required during setup and may appear on account opening paperwork or monthly statements.
• Payroll filings or state registrations: If you’ve hired employees or registered with a state agency, your EIN will be tied to your filings and correspondence.

Where to find your employer’s EIN (with or without a W2)

If you’re working with an external company—whether as a contractor, vendor, or employee—you may also need to locate their EIN for tax filing or verification purposes. 

In most cases, the number is easy to access if you know where to look.

Common places to check:

• W-2 form: If you’ve received wages as an employee, the EIN is listed in Box b of your Form W-2.
• Pay stub or earnings statement: Some employers include the EIN in the header of digital or printed pay stubs.
• Past tax documents: If you’ve filed taxes before using the same employer or client, their EIN may appear on your tax return or IRS transcript.
• Ask your employer directly: HR or payroll departments can typically confirm the number quickly.
• IRS transcript (for employees): You can access your wage and income transcript at IRS.gov, which includes employer EINs reported to the IRS.

Is there a public database for EIN numbers?

EINs are not confidential in the same way SSNs are—but they’re not fully public either. 

There’s no single government-run database where you can look up any business’s EIN. Most private companies’ EINs are not publicly searchable for security and fraud-prevention reasons. 

However, there are a few exceptions—especially for nonprofits and publicly traded companies.

Where EINs are publicly accessible:

• Public companies: If a business is publicly traded, its EIN is often included in SEC filings. You can search for these using the EDGAR database on the SEC’s website.
• Nonprofits and tax-exempt organizations: The IRS provides EINs through its Tax Exempt Organization Search, where you can look up nonprofit entities by name, EIN, or location.
• State business registries: Some states include EINs in public business search tools, though most only display entity IDs or state registration numbers. This varies by state.

Trusted vs untrusted EIN sources

While some third-party websites claim to offer EIN lookups, they often rely on scraped or outdated data—and may charge unnecessary fees. 

When in doubt, use official government sources and verify directly with the business when possible.

SEC EDGAR database

• What you can find: EINs of publicly traded companies via corporate filings
• Is it credible?: Official source

IRS Tax Exempt Organization Search

• What you can find: EINs of nonprofit and tax-exempt organizations
• Is it credible?: Official source

State business entity searches

• What you can find: May include EIN or state ID numbers, depending on the state
• Is it credible?: Varies by state

Third-party EIN lookup websites

• What you can find: Often incomplete or outdated; may charge unnecessary fees
• Is it credible?: Use with caution

Forums or scraped databases

• What you can find: Unreliable and potentially illegal sources of EINs
• Is it credible?: Unreliable

What if you still can’t find your EIN?

If you’ve checked your IRS confirmation letter, business tax returns, or banking records and still can’t find your EIN, you don’t need to reapply. The IRS can resend your number by issuing a Form 147C—just call 800-829-4933 and verify your identity.

You’ll only need a new EIN if your business entity has changed (e.g., moving from sole proprietorship to corporation). If that’s where you are, check out our guide on types of corporations.

Other FAQs about EINs

Is an EIN the same as a Tax ID Number (TIN)?

Yes, an EIN is a type of Taxpayer Identification Number (TIN) used to identify businesses for tax purposes. ​Check out our blog here for more about their differences.

Do I need an EIN if I’m a sole proprietor without employees?

Not necessarily. Sole proprietors without employees or certain tax obligations can use their SSN as their TIN. However, obtaining an EIN can help separate personal and business finances and may be required by some banks or vendors. 

Can I get more than one EIN?

The IRS limits EIN issuance to one per responsible party per day to ensure fair treatment for all taxpayers. ​

Do EINs expire or get reused? 

No, EINs do not expire and are never reused or reassigned to another business entity. Once assigned, an EIN is permanently associated with the entity. ​

Can I look up another company’s EIN, such as a private business?

Not usually. EINs are not searchable for most private companies—so you won’t find a central database. Most businesses don’t publish theirs unless required (e.g., on invoices, tax forms, or public filings).

Is it legal to use someone else’s EIN?

Only if you have explicit authorization. Using or sharing another entity’s EIN without permission can be considered identity fraud under IRS regulations. Always ensure you have proper authorization before using another company's EIN.

What to do once you have your EIN

Once your EIN is in place, you can start taking the next steps to formalize and scale your business—like opening a business bank account, setting up payroll, or applying for credit.

At Rho, we help founders streamline these next steps with a platform designed to handle banking, bill pay, and expense management—all in one place. You’ll need your EIN to get started, and from there, we make it easier to manage your finances with clarity and control.

Book a demo today to see how Rho can support your business as it scales.

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