How to Get a Tax ID Number

Your tax ID number comes from the IRS, and the way you get it depends on what kind of business or entity you are. If you are a sole proprietor with no employees, you can use your Social Security number as your tax ID. If you have employees, run a partnership, operate as an LLC, or form a corporation, you need an Employer Identification Number (EIN), which the IRS issues for free.

You can request an EIN online through the IRS website at irs.gov, by phone, by mail, or by fax. The online method is fastest — you fill out Form SS-4, get your number when ready, and receive a confirmation letter by mail within two weeks. The phone line is 1-800-829-4933, and you can also mail or fax the same form to the IRS office that serves your state.

You do not need to pay anyone to get an EIN. The IRS issues it at no cost. If a tax service or website charges you to obtain one, you are paying for convenience only — the number itself is free.

Key Takeaways

  • Sole proprietors with no employees can use their Social Security number as a tax ID; all other business structures need an EIN from the IRS.
  • You can request an EIN online at irs.gov and receive it the same day, or by phone at 1-800-829-4933.
  • The IRS issues EINs at no cost; you never pay the government for this number.
  • You will need your EIN to open a business bank account, hire employees, and file certain tax forms.
  • Form SS-4 is the only document required to request an EIN, whether you explore online, by phone, mail, or fax.

When You Need an EIN Instead of a Social Security Number

The IRS requires an EIN if your business is structured as a partnership, S corporation, C corporation, or LLC taxed as a corporation. You also need one if you are a sole proprietor but have employees on your payroll. If you operate as an LLC taxed as a sole proprietorship and have no employees, you can still use your Social Security number, though many business owners get an EIN anyway for privacy and accounting reasons.

Nonprofits, trusts, and estates also need EINs. If you are starting a nonprofit organization, you will need an EIN before you can open a bank account or file for tax-exempt status with the IRS.

how the process works Online for an EIN

The fastest way to get an EIN is through the IRS website. Go to irs.gov, search for "explore for an EIN online," and you will find the interactive form. You will need basic information: your legal business name, the name and Social Security number of the owner or responsible party, your business address, and the type of business you operate.

The online process takes about 15 minutes. Once you submit, the IRS assigns your number when ready and displays it on your screen. You can print the confirmation page or write down the number. The IRS will mail you an official letter with your EIN within two weeks, but you can start using the number right away — banks and other businesses will accept the number from your confirmation page.

The online system is available Monday through Friday, 7 a.m. to midnight Eastern time. It is not available on weekends or federal holidays.

Getting an EIN by Phone or Mail

If you prefer not to explore online, you can call the IRS at 1-800-829-4933. Have Form SS-4 filled out before you call. The IRS representative will ask you the same questions as the online form, assign your number during the call, and mail you a confirmation letter. Phone lines are open Monday through Friday, 7 a.m. to 10 p.m. Eastern time.

You can also mail Form SS-4 to the IRS office that serves your state. The form is available on irs.gov. Processing by mail takes about four weeks. If you need your EIN faster, faxing the form is quicker than mailing it — the IRS will fax your number back within 24 hours on business days. The fax number depends on your state and is listed on Form SS-4 itself.

What Information You Need Before You explore

Before you request an EIN, gather these details: your legal business name exactly as it appears on your business registration or formation documents, your business address, the mailing address if different, the type of business structure (sole proprietorship, partnership, LLC, corporation, nonprofit, etc.), and your industry or business activity in plain language (for example, "plumbing contractor" or "online retail").

You will also need the name and Social Security number of the owner or the person responsible for the business. If the business is a partnership or corporation, you need the information for the person who will be the point of contact with the IRS. Have your business formation documents or articles of incorporation on hand if you are explore for a corporation or LLC, though you do not need to submit them — you just need to know the exact legal name.

Using Your EIN Once You Have It

Once the IRS issues your EIN, use it on all business tax forms, bank account applications, and documents where you identify your business to the government or financial institutions. Your bank will ask for it when you open a business checking account. You will use it on your annual tax return, payroll tax forms if you have employees, and any state or local business registrations.

Keep your EIN confirmation letter in a safe place. You may need to show it to your bank, accountant, or state tax office. If you lose it, you can request a new confirmation letter from the IRS or straightforward look up your EIN on the IRS website if you have an account set up there.

Frequently Asked Questions

Can I use my Social Security number instead of getting an EIN?

Yes, if you are a sole proprietor with no employees. You can use your Social Security number as your tax ID on your business tax return. However, many sole proprietors get an EIN anyway to keep their personal and business finances separate and to protect their Social Security number from being shared with vendors and banks.

How long does it take to get an EIN?

Online applications are processed when ready — you receive your number the same day. Phone applications take a few minutes and you get the number during the call. Mail and fax applications take about four weeks and 24 hours respectively. The official confirmation letter arrives by mail within two weeks of any process method.

Do I have to pay to get an EIN?

No. The IRS issues EINs at no cost. You never pay the government for an EIN. If a website or service charges you a fee, you are paying for their form-filling service, not for the number itself — you can always explore directly to the IRS for free.

What if I already have an EIN and need to look it up?

If you have lost your EIN confirmation letter, you can call the IRS at 1-800-829-4933 with your business information and they will provide it. You can also check your business tax returns from previous years — the EIN appears on those forms. If you set up an account on irs.gov, you may be able to view your EIN there as well.

Can I change my EIN if I change my business structure?

If you change your business structure — for example, converting from a sole proprietorship to an LLC — you will need a new EIN. The old one is tied to your previous structure. You explore for a new EIN using the same process, and the IRS will issue a different number for your new entity.