Your federal tax ID number, formally called an Employer Identification Number (EIN), is the nine-digit number the IRS assigned when your business was formed. To find it, check any previously filed federal tax return, your original IRS confirmation notice (CP 575), or your business bank records. If nothing turns up, log into your IRS business tax account online, or call the IRS Business & Specialty Tax Line at 800-829-4933 and ask for a Letter 147C, which serves as an official replacement for the original confirmation.
Look Through Your Own Records First
Before calling anyone, spend ten minutes with documents you already have. The most reliable source is the CP 575 notice the IRS mailed when the EIN was first assigned. The IRS issues that letter only once and will not generate a duplicate, so if you still have it, store it somewhere permanent.1Internal Revenue Service. Sample EIN Confirmation Letter
If the CP 575 is gone, any previously filed federal tax return will show the number near the top: Form 1120 for corporations, Form 1065 for partnerships, or Schedule C for sole proprietors. Businesses with employees can also pull it from quarterly payroll filings on Form 941.2Internal Revenue Service. Form 941 (Rev. March 2026) Employer’s Quarterly Federal Tax Return
Other places the number tends to hide:
- The application you used to open a business bank account, and older bank statements
- Local business license applications
- Payroll service records
- Vendor contracts and W-9s you’ve signed
Any document where you were asked to provide a tax ID during setup is worth a look.
Pull It From Your IRS Business Account
If nothing surfaces in your files, the IRS lets you retrieve the number through a business tax transcript. There are three routes: view it inside your IRS business tax account online, request it by mail on Form 4506-T, or ask for it by phone.3Internal Revenue Service. Get a Business Tax Transcript
The online account is the quickest. Log in, open your entity transcript, and the EIN is on screen. The mail route works but takes longer, and there’s a wrinkle: transcripts requested through Form 4506-T come with the taxpayer identification number masked, which defeats the purpose when the EIN itself is what you’re after.4Internal Revenue Service. About Form 4506-T, Request for Transcript of Tax Return The online account or a phone call is the more practical path.
Call the IRS Business and Specialty Tax Line
For immediate results, call 800-829-4933. The line is staffed Monday through Friday, 7:00 a.m. to 7:00 p.m. in your local time zone; Alaska and Hawaii follow Pacific time.5Internal Revenue Service. Telephone Assistance Contacts for Business Customers – Section: Business and Specialty Tax Line and EIN Assignment (800-829-4933) Work through the automated menu to the option for an existing EIN, and a live agent will verify your identity before reading the number to you.
If a bank or government agency wants written proof, ask the agent to send Letter 147C. That is the IRS’s official EIN verification letter and functions as a replacement for the original CP 575. It can be mailed to the address on file or sent by fax.6Internal Revenue Service. Employer Identification Number Most banks and licensing agencies treat the 147C the same as the original confirmation notice.
What You Need to Verify Your Identity
The IRS will not release an EIN to just anyone who calls. You must be an authorized person for the business, which the IRS calls the responsible party. That usually means a corporate officer, sole proprietor, general partner, managing member of an LLC, or trustee. The agent will ask you to confirm:
- The exact legal business name on the EIN application, not a DBA. Using a DBA will cause the lookup to fail.
- The business address associated with the entity when the EIN was issued or last updated.
- The SSN or ITIN of the person listed as the responsible party.
Under IRC Section 6103, the IRS cannot disclose tax information to someone who isn’t the responsible party on file. A designated representative can access the information, but only with proper authorization filed through Form 2848 (Power of Attorney) or Form 8821 (Tax Information Authorization).7Internal Revenue Service. Power of Attorney and Other Authorizations
When the Responsible Party on File Is No Longer With the Company
This is where a lot of businesses get stuck. The person who originally applied for the EIN left years ago, and nobody on staff matches the name the IRS has on file. When the responsible party changes, the business is required to file Form 8822-B within 60 days of the change.8Internal Revenue Service. Form 8822-B, Change of Address or Responsible Party – Business
If that filing was skipped, you’re in a catch-22: you need the EIN but cannot verify identity because the wrong person is listed. The form must be signed by a current officer, owner, general partner, or authorized representative with an attached power of attorney. There is no specific penalty for failing to file Form 8822-B, but the IRS warns that without a current mailing address and responsible party on file, you may not receive notices of deficiency or demand for tax, while penalties and interest continue to accrue.8Internal Revenue Service. Form 8822-B, Change of Address or Responsible Party – Business
When You Actually Need a New EIN Instead
Not every situation calls for recovering the old number. If your business has gone through a structural change, the IRS may require a brand-new EIN. The general rule: a change to your name, address, or the identity of a trustee or administrator does not require a new number. A change to ownership or structure usually does.9Internal Revenue Service. When to Get a New EIN
Common triggers include a sole proprietor who incorporates or forms a partnership, a corporation that converts to a partnership or sole proprietorship, corporations that merge into a new entity, a partnership that incorporates or dissolves and restarts, and an LLC that terminates and re-forms as a different entity type. Each of those events requires a new EIN. If you have gone through one and are still using the old number, apply for a new EIN online at irs.gov rather than trying to recover the old one.9Internal Revenue Service. When to Get a New EIN
Finding the EIN of Another Business
Sometimes the number you need belongs to someone else: a vendor, an employer, a charity you’re donating to, or a company you’re contracting with. Where to look depends on the type of organization.
Public Companies
The SEC requires publicly traded companies to print their EIN on the cover page of annual (10-K) and quarterly (10-Q) filings.10U.S. Securities and Exchange Commission. Form 10-K Those filings are free through the SEC’s EDGAR database.11U.S. Securities and Exchange Commission. About EDGAR Search by company name and the EIN is on the first page.
Nonprofits
The IRS Tax Exempt Organization Search lets you look up charities and foundations by name or EIN, with links to their Form 990 filings; the EIN appears on the first page of the 990.12Internal Revenue Service. Search for Tax Exempt Organizations One catch: if the nonprofit operates under a DBA, it won’t appear under that name. Search the legal name submitted to the IRS.
An Employer or Client
Employees can pull a current or former employer’s EIN from Box b of any W-2.13Internal Revenue Service. 2026 General Instructions for Forms W-2 and W-3 Independent contractors will find a client’s tax ID in the PAYER’S TIN field on Form 1099-NEC. These forms sit in most people’s old tax files and are easy to overlook.
Private Companies
Private companies are not required to make their EIN public. If you need one for a contract or vendor setup, the standard approach is to ask the company directly through a W-9 request. State-level business filings through the Secretary of State sometimes include an EIN on formation documents, though this varies by state and certified copies typically carry a small fee.