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An EIN (employer identification number) is the IRS’s federal tax ID number for a business. It is free, and an online application issues it immediately. This guide covers how to get one for an LLC or other business, how it differs from a state tax ID number, and where it sits in the setup order for a medical or laboratory supply business.
Quick answer: how to get an EIN for a business
Form the business entity with your state first, then apply for the EIN on the IRS website. The online application is free and issues the number immediately; fax, mail and international phone routes exist for applicants who cannot use it. The IRS states: “You never have to pay a fee for an EIN.” (IRS, checked 2026-11-03.)
What you need
- A formed entity, for an LLC or corporation. The IRS warns that if you do not form your entity with the state first, your EIN application may be delayed.
- A responsible party with an SSN or ITIN. The online application is for a domestic organization with its principal place of business in the U.S. or a U.S. territory, and the applicant must be the responsible party (or an authorized representative) with a Social Security number or ITIN.
- A natural person as responsible party. The Form SS-4 instructions say the responsible party must be an individual, that is, a natural person (government entities are the exception).
- About 15 minutes without interruption. An online session cannot be saved and expires after 15 minutes of inactivity.
Steps to get an EIN online
- Register the business with the state (for an LLC, file the formation documents first).
- Open the IRS “Apply for an EIN online” page. The online application is available only during set hours in Eastern time, so check the IRS page for the current schedule.
- Answer the entity-type questions (see the LLC section below for the choices).
- Submit the application. The EIN is issued immediately online.
- Print or save the confirmation and keep it with the business records.
Only one EIN can be issued per responsible party per day. Beware of websites that charge for an EIN; the IRS and the Small Business Administration both warn against paying for one.
Choose a method: online, fax, mail or phone
| Method | What the IRS says |
|---|---|
| Online | EIN issued immediately; available during set hours (Eastern); responsible party needs an SSN or ITIN. |
| Fax (Form SS-4) | Fax to 855-641-6935; the IRS faxes the EIN back in about 4 business days. |
| Mail (Form SS-4) | Mail to Internal Revenue Service, Attn: EIN Operation, Cincinnati, OH 45999; about 4 weeks. |
| International phone | 267-941-1099 for applicants without a U.S. principal place of business. |
Source for the table: IRS, Employer ID numbers, checked 2026-11-03. The IRS also says the EIN can be used right away to open a bank account or apply for licenses, but allow up to 2 weeks before it works for e-filing, TIN Matching or electronic tax deposits.
How to get an EIN for an LLC
An LLC follows the same online process, and the choices you make map to lines on Form SS-4. The SS-4 instructions (12/2025) say:
- Line 8b: enter the number of LLC members.
- Default tax treatment: a domestic LLC with only one member is disregarded by default; a domestic LLC with two or more members is treated as a partnership.
- Line 9a: a single-member disregarded LLC checks “Other” and writes “disregarded entity”; a multi-member LLC checks Partnership; an LLC that has elected corporate treatment (Form 8832 or 2553) checks the Corporation box.
- Line 7a: the responsible party must be a natural person, so list an individual, not another company.
Your tax treatment is a tax decision. Ask a CPA or enrolled agent before electing anything; this guide does not give tax advice.
Federal tax ID number vs state tax ID number
A federal tax ID number is the same thing as an EIN: the IRS describes an EIN as “a federal tax ID number for businesses, tax-exempt organizations and other entities.” A state tax ID number is issued by a state agency, not the IRS, and is not a substitute for an EIN.
The SBA says an EIN is needed if you pay employees, operate as a corporation or partnership, or file certain tax returns, and that it is also used to open a business bank account and apply for licenses and permits. It adds: “It’s free to apply for an EIN, and you should do it right after you register your business.”
How to get a state tax ID number
Whether you need a state tax ID depends on whether your business must pay state taxes, and the process varies by state. The SBA advises checking with your state government and starting with the state Department of Revenue; it provides a lookup at sba.gov Department of Revenue lookup. Registering for a state tax ID is separate from applying for an EIN, so complete the EIN first and have the confirmation ready.
Where the EIN fits in a medical or lab supply business setup
For a business that plans to sell or resell medical or laboratory supplies, the order below is an editorial sequence built from the sourced steps above. The state-level items differ by state.
- Form the entity with the state (for example, an LLC).
- Get the EIN from the IRS, which the SBA says is used to open a business bank account and apply for licenses and permits.
- Register for state taxes through your state Department of Revenue (the state tax ID).
- Obtain the resale or seller permit your state requires for buying supplies for resale. See resale certificate vs seller’s permit for medical supply businesses and tax-exempt certificates for medical supplies.
- Open the wholesale accounts. The steps are in how to get a wholesale license, and the model is described in wholesale business.
To understand the supply-chain roles you will be applying into, see medical supply wholesaler vs distributor vs manufacturer.
What can go wrong
- Applying before the LLC exists. The IRS warns this may delay the application.
- Paying a third-party site. The IRS and SBA both say not to pay for an EIN.
- Letting the online session time out. It expires after 15 minutes of inactivity and cannot be saved.
- Applying twice. An entity should have only one EIN, and only one EIN is issued per day across all methods. Nominees cannot apply.
- Expecting instant e-file access. Allow up to 2 weeks for e-filing, TIN Matching or electronic tax deposits.
- Losing the number. Check your IRS notice, bank, state or local licensing records and past returns; otherwise call the IRS at 800-829-4933 (Monday to Friday, 7 a.m. to 7 p.m. local time). The IRS cannot cancel an EIN; it can deactivate it.
- Needing a new EIN. The SS-4 instructions give cases such as a sole proprietor who incorporates or enters a partnership, or a change in organization type; a buyer of an existing business generally does not use the former owner’s EIN.
When to get professional help
Ask a CPA, enrolled agent or business attorney if you are unsure which entity type or tax treatment to pick, if the responsible party does not have an SSN or ITIN, if you are buying an existing business, or if you are changing the structure of a business that already has an EIN. State licensing questions go to your state Department of Revenue.
FAQ
How to get an EIN for a business?
Form the entity with the state if it is an LLC or corporation, then apply on the IRS website. The online application is free and issues the EIN immediately; the IRS also accepts Form SS-4 by fax (about 4 business days) or mail (about 4 weeks).
How to get an EIN for an LLC?
Form the LLC with the state first, then apply online as the responsible party, who must be a natural person. Enter the number of members on line 8b; a single-member LLC is a disregarded entity by default and a multi-member LLC is a partnership by default.
How to get a state tax ID number?
Contact your state Department of Revenue. The SBA says whether you need one depends on whether your business must pay state taxes, and the process varies by state.
Is a federal tax ID number the same as an EIN?
Yes. The IRS defines an EIN as a federal tax ID number for businesses, tax-exempt organizations and other entities.
Does it cost anything to get an EIN?
No. The IRS says you never have to pay a fee for an EIN.
Sources
- IRS, Apply for an Employer Identification Number (EIN) online, checked 2026-11-03.
- IRS, Employer ID numbers, checked 2026-11-03.
- IRS, Instructions for Form SS-4 (12/2025), checked 2026-11-03.
- U.S. Small Business Administration, Get federal and state tax ID numbers, checked 2026-11-03.
