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- An EIN identifies a federal tax account
- When an application for an employer identification number is appropriate
- The responsible party must control the entity
- Online, fax, mail, and international procedures
- Form SS-4 asks more than a business name
- When a new EIN is and is not needed
- After the IRS assigns the number
- Sources
Key Facts
- Federal level: An employer identification number is a nine-digit federal tax identifier assigned to a business, estate, trust, nonprofit, or other entity.
- Federal level: The IRS issues EINs without a fee; commercial filing services are optional third parties.
- Federal level: Eligible U.S. applicants can use the IRS online tool, while fax, mail, and international-applicant telephone procedures use Form SS-4 information.
- Federal level: The application must identify the true responsible party rather than a nominee who has only temporary formation authority.
- Federal level: A new EIN is generally tied to a meaningful ownership or entity-structure change, not merely a new business name or address.
- Federal and state: An EIN does not create a state-law entity, license a business, or replace state tax and registration numbers.
An EIN identifies a federal tax account
An employer identification number, or EIN, is a federal taxpayer identification number. Despite the word “employer,” an entity can need an EIN without employees. Partnerships, corporations, many limited liability companies, estates, trusts, tax-exempt organizations, retirement plans, household employers, and some sole proprietors use EINs for federal filing and reporting.
An EIN is not the same as a Social Security number or individual taxpayer identification number. It belongs to the business or other entity for its tax activities. It also does not prove that a state has formed an LLC or corporation, issued a license, approved tax-exempt status, or registered an assumed name.
When an application for an employer identification number is appropriate
A business generally needs an EIN when it hires employees, operates as a partnership or corporation, files certain employment or excise tax returns, or administers specified estates, trusts, or retirement plans. A single-member LLC can need an EIN for employees, excise taxes, or an entity tax election even when it is disregarded for ordinary federal income-tax purposes.
A sole proprietor without employees or special federal filing duties may be able to use the proprietor’s SSN for federal tax reporting. One sole proprietor generally uses one EIN across multiple sole-proprietor businesses and trade names. Forming a partnership or corporation is a different structural event and ordinarily calls for a new number.
The entity should exist under governing state law before the EIN application is submitted. Applying first can create a mismatch if the state rejects or changes the proposed legal name. The legal name on the application should match the formation document, trust instrument, estate name, or individual record that establishes the applicant.
The responsible party must control the entity
The responsible party is the person who ultimately owns or controls the entity or exercises ultimate effective control over it. Except for government entities, the IRS generally requires the responsible party to be a natural person. The application provides that person’s SSN or ITIN, subject to special instructions for eligible foreign applicants.
A nominee is different. A nominee may help form an entity but has little or no authority over its assets and operations. Nominees cannot apply for the EIN or be listed as the responsible party.
A third-party designee may be authorized to receive the newly assigned EIN and answer questions about Form SS-4. That limited authorization requires the applicant’s signature and ends when the EIN is assigned and released. It does not turn the designee into the responsible party.
Online, fax, mail, and international procedures
The IRS online EIN tool is free and generally available to an applicant whose principal place of business, office, agency, or legal residence is in the United States or a U.S. territory. The responsible party or authorized representative completes the application in one session. An approved application produces an EIN and confirmation notice immediately.
The online session cannot be saved and expires after 15 minutes of inactivity. The applicant needs the entity type, formation information, business activity, reason for applying, and responsible-party identification. IRS issuance is limited to one EIN per responsible party per day across all application methods.
Fax and mail applicants submit Form SS-4 using the current destination for their location. The instructions estimate about four business days for a fax response when a return fax number is supplied and about four weeks for mail, while recommending earlier submission. Processing times and addresses can change.
Telephone assignment is reserved for applicants without a legal residence, principal place of business, or principal office or agency in the United States or its territories. The caller must be authorized and able to answer the Form SS-4 questions. Domestic applicants do not receive EINs by telephone.
Form SS-4 asks more than a business name
The form identifies the applicant’s legal and trade names, mailing and physical addresses, responsible party, entity type, formation date, accounting-year closing month, expected employees, principal activity, and reason for applying. Those answers establish the IRS business-tax account and can influence which federal returns the IRS expects.
The reason-for-applying line distinguishes a new business, hired employees, banking purpose, changed organization type, acquired business, estate, trust, pension plan, and other events. Selecting an entity type should reflect federal tax classification, which can differ from an entity’s state-law label. A limited liability company therefore supplies both LLC ownership information and its federal classification.
The guide to federal tax treatment of independent contractors explains one context in which an EIN may be used on information returns. Obtaining an EIN does not itself establish that a worker is an independent contractor or that payments belong on Form 1099-NEC.
When a new EIN is and is not needed
A new EIN is generally associated with a change in ownership or entity structure. A sole proprietor who incorporates or forms a partnership generally needs a new number. A newly created corporation generally has its own EIN, and a partnership that terminates and begins as a new partnership can require another number.
A simple name, address, or location change generally does not require a new EIN. A corporation’s S election alone also does not require a new number. Entity-specific rules matter because a conversion, merger, bankruptcy, ownership change, or trust change can produce different results depending on the legal form.
Changes to the responsible party, mailing address, or business location are reported on Form 8822-B. A responsible-party change must be reported within 60 days. Updating the account preserves the existing EIN rather than replacing it.
After the IRS assigns the number
The confirmation notice is the initial proof of assignment and should be retained with permanent entity records. An EIN can generally be used immediately for federal returns and payments, although some electronic systems may take time to recognize a newly issued number. Bank, payroll, licensing, and vendor systems can impose separate verification processes.
If an EIN is lost, the number may appear on the original notice, prior returns, bank records, or license applications. Authorized persons can also use IRS verification procedures. Applying again merely because the old number is misplaced can create a duplicate account.
An EIN remains permanently associated with the entity. When the entity closes, the IRS may deactivate the business tax account after required returns are filed and taxes are paid, but it does not cancel and reissue the number to another entity.
