EIN vs. Tax ID: What's the Difference and Which One You Need

An EIN and a tax ID are not the same thing, though the terms are often used interchangeably

An EIN (Employer Identification Number) is a specific nine-digit number issued by the IRS to identify a business entity. A tax ID is a broader category that includes several types of identification numbers the IRS uses to track individuals and organizations for tax purposes. An EIN is one kind of tax ID, but not all tax IDs are EINs.

For most people, a Social Security Number (SSN) serves as their tax ID. For businesses, nonprofits, trusts, and certain other entities, an EIN functions as the tax ID. The confusion arises because people sometimes use "tax ID" and "EIN" to mean the same thing when discussing business taxation, but they are technically different categories.

Key Takeaways

An EIN is a nine-digit business identifier issued by the IRS; a tax ID is any number the IRS uses to identify you for tax purposes, including your Social Security Number.
Sole proprietors without employees can use their SSN as a tax ID, but many choose to obtain an EIN to keep business and personal finances separate.
Partnerships, corporations, LLCs, nonprofits, and trusts must have an EIN; they cannot use an owner's SSN as their tax ID.
You can obtain an EIN for free from the IRS online, by phone, or by mail; the process takes minutes online or up to four weeks by mail.
Banks, vendors, and employers will ask for your EIN or tax ID depending on the type of entity you are; providing the wrong number can delay payments or create filing errors.

Types of Tax IDs the IRS recognizes

The IRS uses several different tax identification numbers depending on who or what is being identified. A Social Security Number (SSN) is the tax ID for individuals and sole proprietors. An EIN is the tax ID for businesses structured as corporations, partnerships, or limited liability companies (LLCs). ITINs (Individual Taxpayer Identification Numbers) are tax IDs for noncitizens who do not have an SSN but need to file taxes or open a bank account. Trusts and estates receive an EIN when they need to file their own tax returns.

Nonprofits also receive an EIN, which they use on Form 990 filings and when opening bank accounts. The key distinction is that an EIN always belongs to an entity (a business, trust, or organization), while an SSN or ITIN belongs to a person. If you are self-employed as a sole proprietor with no employees, you can use your SSN as your business tax ID, but you may still choose to obtain an EIN for privacy and accounting reasons.

When you must have an EIN instead of using your SSN

Certain business structures are required to have an EIN and cannot use an owner's Social Security Number as their tax ID. If your business is structured as a corporation (C-corp or S-corp), partnership, or LLC with multiple members, you must obtain an EIN. The IRS will not accept your SSN on business tax forms for these entities.

Nonprofits seeking 501(c)(3) status must have an EIN before they can file for tax-exempt status. Trusts that file their own tax returns must have an EIN. If you hire employees, you must have an EIN to report payroll taxes and file employment tax forms, even if you are a sole proprietor. Banks also typically require an EIN before they will open a business account for a partnership, corporation, or LLC, so you will need one before you can deposit business income.

When you can use your SSN as a business tax ID

If you operate as a sole proprietor with no employees, you can use your Social Security Number as your business tax ID. You would report business income on Schedule C of your personal tax return (Form 1040), and your SSN serves as the identifier. Many sole proprietors do this and never obtain an EIN.

However, even sole proprietors without employees often choose to obtain an EIN for practical reasons. An EIN keeps your business finances separate from your personal finances in the eyes of vendors and banks. It also protects your SSN from being shared with every contractor, client, and vendor who requests a tax ID. If you plan to hire employees in the future, you will need an EIN anyway, so obtaining one early can simplify the transition.

How to obtain an EIN from the IRS

You can obtain an EIN for free through three methods. The fastest is online at IRS.gov: you complete Form SS-4 electronically, receive your EIN immediately, and can print a confirmation letter. This takes about 15 minutes and is available to businesses with a U.S. address.

You can also apply by phone by calling the IRS Business and Specialty Tax Line at 1-800-829-4933. You will need to complete Form SS-4 and have it ready when you call. The IRS will issue your EIN over the phone, and you can request a confirmation letter by mail. This method takes one business day.

A third option is to mail Form SS-4 to the IRS. Processing takes two to four weeks, and you will receive your EIN by mail. This method is slower but works if you do not have internet access or prefer a paper application. You do not need to hire a tax professional or pay a fee; the IRS issues EINs at no cost.

What information you need to provide when applying

To apply for an EIN, you will need to provide your business name, business address, the type of business structure (sole proprietor, partnership, corporation, LLC, nonprofit, trust, etc.), and the reason you are applying (starting a new business, hiring employees, opening a bank account, etc.). If you are applying as an individual sole proprietor, you will provide your name and SSN. If you are applying on behalf of a partnership or corporation, you will provide the name and SSN or EIN of a responsible party (usually an owner or officer).

You will also need to describe your business activity in general terms (for example, "consulting services" or "retail clothing sales"). The IRS uses this information to classify your business for tax purposes. You do not need to have a business license, a registered business name, or any formal paperwork already in place; you can apply for an EIN as soon as you decide to start a business.

How banks and vendors use EINs and tax IDs

When you open a business bank account, the bank will ask for your tax ID. If you are a sole proprietor using your SSN, you provide your Social Security Number. If you have an EIN, you provide that instead. Banks use this number to report interest income and to comply with anti-money-laundering regulations. Providing the wrong number can delay account opening or cause the bank to file incorrect information reports with the IRS.

Vendors, contractors, and clients may also request your tax ID on Form W-9 (for businesses) or Form W-8BEN (for noncitizens). If you are a sole proprietor, you can provide your SSN. If you have an EIN, you provide that. Employers will ask for your tax ID when you start work; if you are self-employed, you provide your SSN or EIN depending on your business structure. Providing the correct number ensures that income is reported under the right entity and prevents filing errors at tax time.

Frequently Asked Questions

Can I use my SSN and an EIN at the same time for the same business?

No. You choose one tax ID for your business. If you are a sole proprietor, you either use your SSN or obtain an EIN, but not both. Once you obtain an EIN, you should use it on all business documents and tax forms, not your SSN. Mixing the two can confuse the IRS and create filing errors.

What if I already have an EIN but want to change my business name?

You do not need a new EIN if you change your business name. The EIN stays with the entity. You simply notify the IRS of the name change by filing Form 8822-B. Your EIN remains the same, and you continue using it on all tax forms and bank accounts.

Do I need an EIN if I am a freelancer or independent contractor?

Not necessarily. If you are a sole proprietor with no employees, you can use your SSN as your tax ID. However, many freelancers obtain an EIN to keep their business and personal finances separate and to avoid sharing their SSN with every client. The choice is yours unless you hire employees, in which case an EIN is required.

How long does it take to receive an EIN by mail?

The IRS typically processes mailed Form SS-4 applications in two to four weeks. You will receive your EIN by mail at the address you provide. If you need an EIN quickly, apply online or by phone instead; both methods provide your EIN the same day or within one business day.

What is the difference between an EIN and a business license?

An EIN is a federal tax identification number issued by the IRS. A business license is a local or state permit that authorizes you to operate a business in a specific location. You may need both, but they serve different purposes. The EIN is for tax reporting; the business license is for regulatory compliance with your city or state.

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.