To find your EIN number, start with the CP 575 notice the IRS mailed when it first assigned the number, then check any federal tax return your business has filed, and then your business bank account paperwork or state license records. If none of those turn up the number, request an IRS business tax transcript online or call the IRS Business and Specialty Tax Line at 800-829-4933 and a representative will give it to you over the phone after verifying your identity.
Look Through Your Own Records First
The single most authoritative document is the CP 575 notice, formally titled “Notice of New Employer Identification Number Assigned,” which the IRS issues when it approves a new EIN application.1Internal Revenue Service. IRM 21.7.13 Assigning Employer Identification Numbers If you applied online, you may have saved or printed it at the end of the session. If you applied by mail or fax, the IRS mailed a paper copy. Check permanent business files, formation binders, or a safe deposit box.
If the CP 575 is gone, your prior federal tax returns are the next best source. The EIN doesn’t change, so any copy works, paper or electronic. Corporations report it on Form 1120, and partnerships on Form 1065.2Internal Revenue Service. Instructions for Form 1120 (2025) Sole proprietors who obtained an EIN will find it on the Schedule C attached to their Form 1040.
A few other places the number typically lives:
- Quarterly payroll filings. Form 941 requires the EIN in the header so the IRS can credit tax deposits properly.3Internal Revenue Service. Instructions for Form 1065 (2025)
- Business bank account paperwork. Your original account agreement or signature card should show the EIN.
- State and local business licenses or professional permits, which often print the federal EIN on the application or the permit itself.
- Accounting or payroll software. The number is usually stored on the company profile or tax-settings screen.
Ask Your Bank or Licensing Agency
If nothing in your files works, the outside organizations that already have the number can hand it back to you. The IRS specifically points to these external steps before calling the agency itself.4Internal Revenue Service. Employer Identification Number
Your bank is usually the fastest call. Federal rules require an EIN to open a business checking or savings account, so the bank has it on file.5U.S. Small Business Administration. Get Federal and State Tax ID Numbers Contact your branch or the bank’s business banking line, verify yourself as an account holder, and ask for the EIN.
State or local agencies where you registered the business or applied for a license may also have the number, and many jurisdictions let you look up a business registration through a free online portal without making a call at all.
Get a Business Tax Transcript Online
The IRS lets you retrieve the number without calling. The “Get a Business Tax Transcript” service provides a record of your business tax account, which includes the EIN.4Internal Revenue Service. Employer Identification Number You can also sign in to the Business Tax Account portal after verifying your identity through the agency’s third-party authentication provider.6Internal Revenue Service. Business Tax Account One catch: registering for a Business Tax Account itself requires the EIN, so this route works best if you set the account up before losing track of the number.
Call the IRS at 800-829-4933
When self-service doesn’t work, the IRS will give you the EIN over the phone. Call 800-829-4933, the Business and Specialty Tax Line, Monday through Friday, 7:00 a.m. to 7:00 p.m. local time. Callers in Alaska and Hawaii follow Pacific time.7Internal Revenue Service. Telephone Assistance Contacts for Business Customers Work the automated menu to the option for an existing EIN inquiry to reach a live representative.
Once your identity is verified, the representative can read out the EIN on the call. If you also need a written confirmation for a bank, a lender, or another third party, ask for Letter 147C, “EIN Previously Assigned.” The IRS cannot reissue the original CP 575, so Letter 147C is the official replacement.1Internal Revenue Service. IRM 21.7.13 Assigning Employer Identification Numbers You can receive it by fax while still on the phone or by mail, which typically takes four to six weeks.
Who Is Allowed to Ask, and What You’ll Need
Under IRC Section 6103, the IRS generally cannot release return information to anyone who is not authorized.8Internal Revenue Service. Disclosure Laws Only a person with legal authority over the business can call. Depending on entity type, that means:
- Sole proprietorship: the owner.
- Partnership: a partner named on the most recent return.
- Corporation: a corporate officer listed in IRS records.
- Trust or estate: the trustee or executor.
Before the call, have three things ready:
- The exact legal business name, including suffixes like “LLC” or “Inc.”
- The business address shown on your most recent filing.
- The Social Security Number or Individual Taxpayer Identification Number of the authorized person, which the IRS checks against the original EIN application.
If anything has changed since the last filing, verification may take longer, so having the older address handy helps.
Sending Someone Else to Make the Call
A CPA, attorney, or other representative can contact the IRS on your behalf if you file Form 2848, Power of Attorney and Declaration of Representative, first. That form lets the named individual inspect and receive confidential tax information, and the IRS records most Form 2848 authorizations on its Centralized Authorization File so the representative doesn’t have to resubmit paperwork for later calls.9Internal Revenue Service. Instructions for Form 2848 Power of Attorney and Declaration of Representative If you only need someone to receive information without full representational authority, Form 8821 (Tax Information Authorization) is a lighter alternative.8Internal Revenue Service. Disclosure Laws Either form must be on file before the representative calls. The IRS will not release information to an unauthorized third party on the spot.
If You’re Looking Up a Different Company’s EIN
The methods above only work for your own business. If you need a nonprofit’s EIN for a donation receipt or grant, use the IRS Tax Exempt Organization Search, which returns the EIN by name.10Internal Revenue Service. Search for Tax Exempt Organizations Publicly traded companies list their EIN on the cover page of Form 10-K in the SEC’s EDGAR database.11SEC.gov. Form 10-K For a private company, there is no public database. Ask the company directly, or request the number on Form W-9, the standard form businesses use to share taxpayer identification numbers with parties that need to report payments.
Why Getting the Right Number Matters
Filing information returns like Forms W-2 or 1099 with the wrong EIN triggers penalties. Federal regulations treat an incorrect taxpayer identification number as a failure that is never considered minor or inconsequential, so penalties apply automatically.12eCFR. 26 CFR 301.6721-1 – Failure to File Correct Information Returns The per-return amount is smaller if you correct the error within 30 days of the filing deadline, larger if the error runs to year-end, and larger still (with the annual cap removed) if the IRS finds the wrong number was used intentionally. Amounts are adjusted for inflation each year, so check the current IRS penalty tables.
An incorrect EIN also causes practical headaches: payroll tax deposits credited to the wrong account, delayed W-2 processing for employees, and IRS notices that take time to resolve. Confirming the correct number before filing season is much cheaper than fixing it afterward.