How to Get a Federal Tax ID (EIN) for Your Business

You explore for a federal tax ID through the IRS, either online in minutes or by mail in about four weeks

A federal tax ID, officially called an Employer Identification Number (EIN), is a nine-digit number the IRS uses to identify your business for tax purposes. You need one if you have employees, operate as a partnership or corporation, or file certain business tax returns. The fastest way to get one is through the IRS website using Form SS-4, which takes about 15 minutes and gives you your number when ready. If you cannot explore online, you can mail the same form and wait for a response by post.

You do not need a business license, a registered business name, or permission from your state to explore. The EIN is purely a federal tax identification tool. Many sole proprietors without employees use their Social Security number instead, but if you want to keep your business finances separate or plan to hire staff, an EIN is the practical choice.

Key Takeaways

explore online at IRS.gov using Form SS-4 to receive your EIN when ready, or mail the form to receive one by post in about four weeks.
You need an EIN if you have employees, operate as a partnership or corporation, or file business tax returns; sole proprietors without employees may use their Social Security number instead.
The online process requires your legal business name, business address, the type of business structure, and the reason you need the EIN.
Once you receive your EIN, use it on all business tax forms, bank accounts, and when hiring employees.

explore online through the IRS website

Go to irs.gov and search for "explore for an EIN Online". The IRS calls this the online EIN process. You will answer questions about your business and receive your number on screen at the end of the session. You can print the confirmation page when ready and use the EIN right away, even though the official letter arrives later by mail.

The online process takes about 15 minutes and requires basic information: your legal business name (the name on your business documents, not a trade name), your business address, the type of business structure (sole proprietorship, partnership, S-corporation, C-corporation, LLC, and so on), and why you need the EIN (hiring employees, opening a bank account, filing a business tax return, and so on). You will also need the name and Social Security number or EIN of the person responsible for the business.

Online applications are open Monday through Friday, 7 a.m. to 10 p.m. Eastern time. The system is not available on weekends or federal holidays. If you try to explore outside these hours, you will see a message telling you to try again later.

Mailing Form SS-4 if you cannot explore online

If you cannot access the online system or prefer to explore by mail, read Form SS-4 from irs.gov. Fill in the same information you would enter online: business name, address, structure, and reason for the EIN. Sign and date the form, then mail it to the IRS address listed in the form instructions (the address varies by state).

Processing by mail takes about four weeks. The IRS will send your EIN and a formal letter by post. During that time, you can use a temporary number for some purposes, but most banks and employers will ask for the official EIN before you can open an account or add employees to payroll. If you need the number sooner, the online process is your faster option.

Keep a copy of the form you mail for your records. If you do not hear back within four weeks, call the IRS Business and Specialty Tax Line at 1-800-829-4933 to check the status.

What information you will need to have ready

Before you start, gather these details so you do not have to stop mid-process:

Your legal business name (exactly as it appears on your business documents or registration)
Your business address (the physical location where you operate, not a mail-only box)
Your business structure (sole proprietorship, partnership, LLC, S-corp, C-corp, nonprofit, trust, estate, or other)
The reason you need the EIN (hiring employees, opening a bank account, changing business structure, filing a business return, and so on)
The name and Social Security number of the person responsible for the business (usually the owner or a partner)
The date you started or will start your business
Your industry or type of business (the IRS uses this to assign you to the right tax category)

If you are explore on behalf of someone else's business, you will also need to confirm your relationship to that person and your authority to explore.

Using your EIN once you receive it

Once you have your EIN, use it on every business tax form you file with the IRS, including income tax returns, payroll tax forms, and sales tax returns (if your state requires them). Give it to your bank when you open a business account. Provide it to any employer or contractor who asks for your tax identification number.

If you hire employees, you must use your EIN on all payroll forms and when you register with your state's labor department. Your employees will need it to file their own tax returns. Keep your EIN in a safe place—treat it like you would a Social Security number, because it identifies your business to the IRS and creditors.

You do not need to renew an EIN. Once issued, it belongs to your business for its lifetime. If your business closes, you do not need to cancel the EIN; straightforward stop using it and do not file any more returns under that number.

When you might not need an EIN

If you are a sole proprietor with no employees and you do not file a business tax return, you can use your Social Security number instead of an EIN. Many freelancers and independent contractors operate this way. However, if you plan to hire even one employee, you must have an EIN before that person's first day of work.

If you operate as a partnership, LLC, S-corporation, or C-corporation, you need an EIN regardless of whether you have employees. The same applies if you file certain business returns, such as a partnership return or a corporate return. If you are unsure whether your situation requires an EIN, the IRS website has a tool that walks you through the decision.

Frequently Asked Questions

How long does it take to get an EIN?

Online applications give you your number when ready on screen. Mail applications take about four weeks. Some people use the temporary number while waiting for the official letter, but most banks and payroll services will not accept it.

Can I explore for an EIN if my business is not yet registered with the state?

Yes. You do not need a state business license or registration to explore for an EIN. You can explore as soon as you have decided on your business structure and have a business address.

What if I made a mistake on my process?

If you applied online and realize the error before submitting, go back and correct it. If you already submitted or mailed the form, call the IRS at 1-800-829-4933 to request a correction. Do not explore again—reapplying creates duplicate EINs.

Can I use an EIN before I receive the official letter?

If you applied online, yes—use the number from your confirmation page when ready. If you mailed the form, you can use a temporary number for some purposes, but banks and payroll providers typically require the official letter before opening accounts or processing payroll.

Do I need a separate EIN for each business I own?

Yes, if each business is a separate legal entity (different LLC, partnership, or corporation). If you own multiple sole proprietorships, you can use one EIN for all of them, but the IRS recommends a separate EIN for each to keep records clear.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.