How Do I Find My Federal ID Number?

A Federal ID Number, more formally known as an Employer Identification Number (EIN), is a unique nine-digit number the Internal Revenue Service (IRS) assigns to businesses. This number serves as a primary identifier for a business, much like a Social Security number does for an individual. It is used for functions including filing federal tax returns, paying employees, and opening a business bank account. Any business that operates as a corporation or partnership, or that has employees, is required to have an EIN.

Locating the Number on Existing Documents

The most direct method for finding a misplaced EIN is to review your existing business records. The original notice you received from the IRS when your number was first assigned, Form CP 575, is the most definitive source. The IRS does not reissue this form, but if you have lost it, you can call the IRS and request an EIN Verification Letter (147C).

If that notice is unavailable, your prior year’s federal tax returns are the next best place to look, as the EIN is prominently displayed on these forms. For corporations, it will be on Form 1120; for partnerships, it’s on Form 1065; and for sole proprietors who have an EIN, it can be found on Schedule C (Form 1040).

Your business banking records also serve as a reliable source for your EIN. Financial institutions require this number to open a business bank account, and it is often printed on account statements or accessible through your online banking portal. Applications for business loans will also contain your EIN, as lenders need it for their records. Finally, review any federal, state, or local licenses and permits your business holds, as these documents often require the EIN.

Calling the IRS Business & Specialty Tax Line

Should your search through business documents prove unsuccessful, the next step is to contact the IRS directly. The IRS will only disclose this sensitive information to an individual who is properly authorized, such as a sole proprietor, a partner in a partnership, or a corporate officer. Before making the call, you must gather specific information to verify your identity.

To confirm you are a responsible party, be prepared to provide the following information:

• The full legal name of the business entity
• The principal business address on file with the IRS
• The type of business entity (e.g., corporation, partnership, sole proprietorship)
• Your name and title within the business

With this information ready, you can call the IRS Business & Specialty Tax Line at 1-800-829-4933. The line is open from 7:00 a.m. to 7:00 p.m. local time, Monday through Friday. An IRS representative will ask you questions to validate your identity and your role within the company before providing the EIN over the phone.

Handling a Lost or Misplaced Number

It is important that you do not apply for a new EIN simply because it was misplaced. An EIN is a permanent number, and a new one is only required if the business changes its ownership or structure, for example, when converting from a sole proprietorship to a corporation.

Applying for a second EIN for the same active business can create complications, including confusion in tax records, problems with filing returns, and difficulties in processing payments, which can lead to notices and penalties from the IRS. The existence of multiple EINs for a single entity complicates the tracking of tax obligations and payments.