Whether you’re filing taxes, opening a business bank account, or applying for a loan, your Employer Identification Number (EIN) is one of the most important identifiers your business has. Knowing how to find your EIN number and what to do when you’ve lost it can save you hours of frustration and prevent costly delays.
The experts at Aiccountingpros walk you through everything you need to know: what an EIN is, why you need it, where to look for it on official IRS documents, how to recover a lost EIN, and even how to find another company’s EIN number for legitimate business purposes.
What Is an EIN Number?
An Employer Identification Number (EIN) is a unique nine-digit number assigned by the Internal Revenue Service (IRS) to identify a business entity for federal tax purposes. It follows the format XX-XXXXXXX and functions like a Social Security Number (SSN) but for your business rather than for you as an individual.
Learn more about the key differences by reading our guide Is EIN and TIN the Same?
It is important to understand that using the wrong term on a tax form, loan application, or bank paperwork can cause delays, rejected filings, or even compliance penalties. Always confirm which specific identifier is being requested.
The IRS uses your EIN to track your business’s tax obligations, payroll reports, and compliance records. Other terms you may hear that all refer to the same number include:
| Term | What It Means |
| EIN | Employer Identification Number most common term |
| FEIN | Federal Employer Identification Number same as EIN |
| Federal Tax ID | Used interchangeably with EIN in banking and legal contexts |
| TIN | Taxpayer Identification Number is an umbrella term; EIN is a type of TIN |
It is important to understand that using the wrong term on a tax form, loan application, or bank paperwork can cause delays, rejected filings, or even compliance penalties. Always confirm which specific identifier is being requested.
Why You May Need to Find Your EIN
There are dozens of everyday business situations where you’ll be asked to provide your EIN. Understanding these scenarios helps you appreciate why keeping your EIN easily accessible is not optional; it’s essential.
Common Reasons Business Owners Need Their EIN
- Filing federal and state business tax returns
- Opening a dedicated business bank account
- Applying for business loans, lines of credit, or business credit cards
- Hiring employees and setting up payroll
- Obtaining business licenses and permits
- Registering for state sales tax or use tax
- Working with vendors who need to verify your business identity
- Applying for government contracts or grants
- Filing for tax-exempt status (nonprofits)
- Responding to IRS notices or audits
Even sole proprietors and single-member LLCs that don’t have employees may need an EIN, for example, when opening a business bank account or working with certain payment processors. Many financial institutions require an EIN as part of their Know Your Business (KYB) protocols, especially in 2025, as regulatory frameworks have tightened.
If you work as an independent contractor, you might be wondering whether you actually need one. Read our detailed article Do Independent Contractors Need an EIN?
How to Find Your EIN Number on IRS Documents
The most reliable places to find your EIN are official IRS-issued documents and your own business records. Below is a detailed breakdown of each source:
1. IRS CP 575 Confirmation Letter
When the IRS assigns your EIN, it mails you a CP 575 confirmation letter. This is the original, one-time official record of your EIN. The letter will clearly display your nine-digit number in XX-XXXXXXX format.
- Keep this letter permanently in your business records
- It is the only original confirmation the IRS will ever issue
- If you lose it, you must request a 147C letter instead (see Recovery section)
2. Previous Federal Business Tax Returns
Your EIN appears on every federal tax return your business has filed. Check any of the following forms:
| Tax Form | Used By |
| Form 1120 | C Corporations |
| Form 1120-S | S Corporations |
| Form 1065 | Partnerships |
| Schedule C (Form 1040) | Sole Proprietors / Self-Employed |
| Form 941 / 940 | Employers (Payroll Tax Returns) |
3. W-2 and 1099 Forms
If you are an employee trying to find your employer’s EIN, for example, when filing your personal income taxes, look at Box b of your W-2 form. The number appears as a nine-digit code in XX-XXXXXXX format, usually printed just above or below your employer’s name. Many employers also include their EIN directly on pay stubs.
4. Business Bank Account Documents
Most banks require your EIN when you open a business account. Check your original account-opening paperwork, statements, or loan documents. Your EIN is typically recorded in the bank’s records and may appear on certain official correspondence.
5. State Business Filings and Licenses
When you registered your business with the state or applied for a business license, your EIN was likely included in those filings. Check your state’s Secretary of State business registry or your license application paperwork.
How to Recover a Lost EIN Number
Losing track of your EIN does not mean starting over. The IRS maintains your EIN permanently once it has been issued; it will never be canceled or reassigned to another business. Here is exactly how to recover a lost EIN number:
Step 1: Check Your Internal Records First
Before contacting the IRS, conduct a thorough internal search. Many business owners find their EIN in an unexpected place.
Common spots to check:
- Your original IRS CP 575 confirmation letter
- Previously filed tax returns (digital or paper copies)
- Business bank account opening documents
- Business loan applications or credit card agreements
- Payroll records or previous W-2s issued to employees
- Accounting software (QuickBooks, FreshBooks, Xero, etc.)
- Email inbox search for “EIN” or “Employer Identification Number.”
Step 2: Call the IRS Business & Specialty Tax Line
If internal records come up empty, call the IRS directly. This is the most reliable method for recovering a lost EIN.
| Detail | Information |
| Phone Number | 1-800-829-4933 |
| Hours | Monday – Friday, 7:00 a.m. to 7:00 p.m. local time |
| Who Can Call | Authorized individual (owner, officer, or authorized representative) |
| What You Get | IRS will issue a 147C EIN Verification Letter by mail or fax |
The 147C EIN Verification Letter serves the same legal and banking purpose as the original CP 575 confirmation letter. Banks, lenders, and government agencies accept it without issue.
Watch Out for Scams
- The FTC has issued warnings about scammers impersonating IRS agents who charge fees for EIN lookups or recovery.
- The IRS will NEVER charge you to look up or retrieve your existing EIN.
- EIN lookup and recovery through official IRS channels is completely free.
- If you are charged a fee by a third-party service claiming to be the IRS, report it to the FTC immediately.
Common EIN Lookup Methods
Depending on your situation, different lookup methods will work better than others. The table below summarizes the most common EIN lookup methods and their key characteristics:
| Method | Best For | Speed | Cost |
| CP 575 Letter | Business owners who kept the original IRS letter | Instant | Free |
| Prior Tax Returns | Businesses with a filed tax history | Minutes | Free |
| Business Bank Records | Account holders with original bank documents | Minutes | Free |
| IRS Business Tax Line | Lost EIN with no backup records | Same day (phone) | Free |
| 147C Verification Letter | Official verification needed for banking/legal | Days (fax) or Weeks (mail) | Free |
| Accounting Software | Businesses using digital bookkeeping tools | Instant | Free |
| W-2 / Pay Stub | Employees finding the employer’s EIN | Instant | Free |
One important note: the IRS does not maintain a public online database where individuals can search for EINs. All lookups of your own EIN must go through the methods listed above
How to Find Another Company’s EIN Number
There are many legitimate reasons why you might need to look up another company’s EIN. Common scenarios include conducting due diligence before entering a business partnership, verifying a vendor’s identity for compliance, preparing a Form 1099, or researching a company for investment purposes.
It is legal to look up EINs through legitimate public channels. What is not legal is using another company’s EIN to misrepresent your authority over that business, open fraudulent accounts, or file false tax returns.
Here are the main methods for finding another company’s EIN:
1. Request a Form W-9 Directly
The simplest and most professional way to obtain another company’s EIN is to ask them directly for a completed Form W-9. This is standard practice in business-to-business transactions, especially when you need to issue a Form 1099 at year-end. Most legitimate businesses will provide this readily.
2. Search SEC EDGAR for Publicly Traded Companies
Any company registered with the Securities and Exchange Commission (SEC) is required to include its tax ID number in its public filings. The SEC’s EDGAR (Electronic Data Gathering, Analysis, and Retrieval) system is entirely free to search.
- Visit www.sec.gov/edgar
- Search by company name or stock ticker symbol
- Look for filings such as Form 10-K (annual report) or Form 10-Q (quarterly report)
- The EIN is typically listed as “IRS Number” in the header section of these filings
- Registration statements (Form S-1) and proxy statements may also contain the EIN
This method works exclusively for publicly traded companies. Private companies do not file with the SEC and therefore will not appear in EDGAR.
3. Use the IRS Tax Exempt Organization Search for Nonprofits
For nonprofit organizations, the IRS provides a free public search tool called the Tax Exempt Organization Select Check. You can look up any charity, foundation, or tax-exempt organization by name to find its EIN and verify its tax-exempt status. This is available at apps.irs.gov/app/eos.
Nonprofits are also required to file Form 990, which is a public document. Tools like ProPublica’s Nonprofit Explorer provide free, searchable access to Form 990 data, including EINs.
4. Check State Business Registries and Public Records
For private companies that are not SEC-registered, local and state public records can sometimes yield EIN information. When a business applies for a state business license, local permits, or professional licenses, the EIN may be included in those filings. Many state Secretary of State websites offer free business entity searches.
- Search your state’s Secretary of State business registry by company name
- Check county or city clerk filings for local business license applications
- Review UCC (Uniform Commercial Code) filings, which sometimes include EINs
5. Review Business Credit Reports
Business credit reporting agencies such as Dun & Bradstreet, Experian Business, and Equifax Business collect and publish business information, including EINs. While these reports typically require a subscription or fee, they can be a valuable resource when other free methods haven’t worked.
| Company Type | Best Lookup Method | Tool / Resource |
| Public Company | SEC EDGAR Filing Search | sec.gov/edgar |
| Nonprofit Organization | IRS Exempt Org Search + Form 990 | apps.irs.gov/app/eos |
| Private Company | Request Form W-9 directly | Direct business contact |
| Any Business | Business credit report | Dun & Bradstreet, Experian Business |
| State-Registered Business | State business registry | Secretary of State website |
Conclusion
Finding and managing your Employer Identification Number (EIN) doesn’t have to be complicated. Whether you’re a new business owner or need to recover a lost EIN, keeping this critical identifier accessible will save you time, reduce stress, and help you maintain full compliance with banks, lenders, and the IRS.
If you need professional assistance with tax filings, EIN-related documentation, bookkeeping, or business financial setup, the team at Aiccountingpros is here to help.
FAQs
Q1.Can I look up an EIN number online?
Generally, no. The IRS does not provide a public online EIN lookup tool for business owners to search for their EIN.
Q2.Can I find my EIN without my W-2?
Yes. You can find your EIN on tax returns, business bank documents, IRS notices, or other official business records.
Q3.How do I retrieve a copy of my EIN number?
Check your EIN confirmation letter, tax documents, or contact the IRS Business & Specialty Tax Line for assistance.
Q4. Can I apply for a new EIN if I lose mine?
No. Your EIN remains permanently assigned to your business. If lost, retrieve it through your records or the IRS instead of applying for a new one.
Q5. Is an EIN the same as a Social Security Number?
No. An EIN identifies a business, while an SSN identifies an individual. They are separate numbers used for different purposes.
Q6. Does my EIN ever expire or change?
No. An EIN is permanent and does not expire. However, certain business structure changes may require a new EIN.
Q7. Can I find my EIN online through the IRS website?
No. The IRS does not offer an online EIN lookup tool. You must check your records or contact the IRS for assistance.
Q8. Do I need an EIN if I am a sole proprietor with no employees?
Not always, but it is often recommended. An EIN can help with banking, vendor requirements, and separating personal and business finances.
