Contents:
- Brief Intro: What a Tax ID Number Actually Is
- Preparation: What You’ll Need to Search
- Finding Your Own Business Tax ID Number
- Check Your EIN Confirmation Letter
- Review Past Tax Returns
- Check Bank Records
- Look at Business Licenses and Permits
- Call the IRS Business & Specialty Tax Line
- Finding Another Company’s EIN
- What the Pros Know
- A Real-World Example
- Seasonal Timing Note
- Frequently Asked Questions
- Is my EIN the same as my Social Security Number?
- Can I look up any business’s EIN online for free?
- What if I never received an EIN confirmation letter?
- How long is an EIN valid?
The accountant asks for your EIN during a routine call to set up a new vendor account, and suddenly you are digging through old drawers and email folders, unable to remember where you filed it three years ago. It is one of the most common small business scrambles, and thankfully, one of the easiest to fix once you know where to look.
Brief Intro: What a Tax ID Number Actually Is
A business Tax ID Number, formally called an Employer Identification Number (EIN), is a nine-digit number the IRS assigns to identify your business for tax purposes, similar to a Social Security number for a company. You need it for filing taxes, opening bank accounts, applying for licenses, and hiring employees.
Preparation: What You’ll Need to Search
- Access to old tax returns or IRS correspondence
- Your business’s formation documents, if an LLC or corporation
- Bank account records if you used the EIN to open one
- Patience if calling the IRS, since hold times can run 30-45 minutes
Finding Your Own Business Tax ID Number
1. Check Your EIN Confirmation Letter
When the IRS issued your EIN, they sent Form CP 575. Search your email if you applied online, since the IRS provides an immediate downloadable confirmation, or check physical mail records from the application date.
2. Review Past Tax Returns
Your EIN appears on every business tax return filed, including Form 1120, 1065, or Schedule C. Check the top of the first page of your most recent filing.
3. Check Bank Records
If you opened a business bank account, the bank required your EIN during setup. Contact your bank, or check your original account opening documents.
4. Look at Business Licenses and Permits
Many state and local licensing applications require an EIN, and it often appears on the approved license document itself.
5. Call the IRS Business & Specialty Tax Line
If all else fails, call 800-829-4933, Monday through Friday, 7 a.m. to 7 p.m. local time. Only an authorized person (owner, partner, officer) can request this, and the IRS verifies identity first.
Finding Another Company’s EIN
Looking up a vendor’s or another business’s EIN requires different methods, since the IRS does not release this to the public directly. Publicly traded companies list their EIN in SEC filings, searchable free through the SEC’s EDGAR database. Nonprofit EINs are searchable through the IRS Tax Exempt Organization Search tool, also free. For private companies, your best option is asking the business directly or checking a signed W-9 they provided for a contract.
What the Pros Know
A Real-World Example
A bakery owner in Denver needed her EIN to apply for a small business loan but had misplaced her confirmation letter after a move. She found it in under ten minutes by pulling up last year’s Schedule C, which listed the number on line D.
Seasonal Timing Note
January through April is peak tax season, meaning IRS phone lines are significantly busier, with hold times sometimes exceeding an hour. If you can search your own records first rather than calling, you will save considerable time during this window.
Frequently Asked Questions
Is my EIN the same as my Social Security Number?
No, they are separate numbers, though sole proprietors without employees can sometimes use their SSN for tax filing instead of an EIN.
Can I look up any business’s EIN online for free?
Only for public companies (via SEC EDGAR) and registered nonprofits (via IRS Tax Exempt Organization Search); private company EINs are not publicly searchable.
What if I never received an EIN confirmation letter?
Call the IRS Business & Specialty Tax Line at 800-829-4933 to request a replacement confirmation, known as Letter 147C.
How long is an EIN valid?
An EIN never expires and stays tied to your business entity permanently, even during periods of inactivity.
