- What is an EIN?
- Who needs a federal EIN?
- Benefits of getting an employer identification number
- What information you need for EIN registration
- How to apply for a free EIN online
- Common EIN application mistakes
- How to get an EIN by mail, fax, or phone
- When you need a new EIN
- How to look up your EIN
- Apply for the Ramp Corporate Card using only your EIN
AI Summary
Getting an EIN is completely free and takes just a few minutes through the IRS website. An employer identification number (EIN) is what the IRS uses to identify your business for tax purposes, and you'll need one before you can open a business bank account, hire employees, or apply for financing.
What is an EIN?
An EIN is a unique nine-digit tax identification number that the IRS assigns to US businesses. It's formatted with a dash between the second and third digits: XX-XXXXXXX. You may also see it referred to as a federal EIN or federal tax ID number.
When you apply for a business loan or line of credit, the lender pulls your business credit report using your EIN, not your Social Security number. Without an EIN on file, most banks won't even open a business checking account for you, let alone approve a credit application.
Who needs a federal EIN?
Most businesses need an EIN to operate legally. Even if you're not strictly required to have one, many owners choose to get an EIN for financing, banking, and tax benefits. Here's who the IRS says must have one.
| Entity type | EIN required? | Notes |
|---|---|---|
| Sole proprietor (no employees) | No | Optional, but recommended for banking and credit |
| Single-member LLC (no employees) | No | Most still apply for banking and credit purposes |
| Multi-member LLC or partnership | Yes | IRS treats as separate taxpayer |
| Corporation (C-corp or S-corp) | Yes | Required from incorporation |
| Non-profit organization | Yes | Needed for tax-exempt status |
| Trust or estate | Yes | Required for income/distribution tracking |
Businesses with employees
Any business that hires employees must obtain an EIN for payroll tax purposes. You'll use it to report wages, withhold taxes, and file employment tax returns with the IRS. If you plan to bring on even one W-2 worker, an EIN is non-negotiable.
LLCs and partnerships
Multi-member LLCs and partnerships require an EIN regardless of whether they have employees. The IRS treats these entities as separate taxpayers, so each one needs its own identification number. Single-member LLCs without employees aren't required to have an EIN, but many still apply for one to simplify banking and build business credit.
Corporations and S-corps
All corporations, both C corps and S corps, must have an EIN for tax filing and compliance. You'll need it from the moment you incorporate, well before you file your first return.
Non-profit organizations
Non-profits need an EIN to apply for tax-exempt status and accept tax-deductible donations. You'll also use it when filing Form 990 and other required IRS documents.
Trusts and estates
Trusts and estates that manage assets and distribute income need an EIN for tax reporting. If you're administering an estate or managing a trust, the IRS requires a separate identification number to track income and distributions properly.
Benefits of getting an employer identification number
Even if you're not legally required to have an EIN, there are several practical advantages to getting one early.
Separate business and personal finances
An EIN lets you open a business bank account and apply for business credit without using your Social Security number. This creates a clear boundary between your personal and business finances, which simplifies bookkeeping and protects your personal assets.
Build business credit
Your EIN is the foundation of your business credit profile. Lenders, suppliers, and creditors report activity under your EIN, building a credit history separate from your personal score. Some business credit cards, including EIN-only cards, don't require a personal credit check at all. You can start building business credit immediately without impacting your personal profile.
Access business banking and financing
Most banks require an EIN to open a business checking account. Lenders and investors will also ask for your EIN during due diligence, so having one ready means fewer delays when you need working capital. Some lenders offer EIN-only approval for business credit cards and lines of credit, letting you access financing based solely on your business's financial health.
Protect your Social Security number
Every time you hand over your SSN for a business transaction, you increase your exposure to identity theft. An EIN replaces your SSN on tax forms, vendor applications, and bank paperwork, reducing the number of places your personal information lives.
Hire employees
You can't run payroll without an EIN. The IRS requires it to track employee wages, tax withholdings, and contributions. If you plan to hire, get your EIN first so you can set up payroll systems without delay.
What information you need for EIN registration
Before you start your application, gather the following details:
- Legal business name: Your business name as registered with your state
- Business address: Your physical business location, not a P.O. box
- Responsible party: The name and SSN or ITIN of the person who controls the entity
- Entity type: Limited liability company (LLC), corporation, partnership, sole proprietor, etc.
- Reason for applying: Starting a new business, hiring employees, banking purposes, etc.
- Business start date: When you started or acquired the business
How to apply for a free EIN online
The online application is the fastest method: you'll receive your EIN immediately upon completion. The IRS EIN Assistant is available Mon–Fri, 7am–10pm ET.
1. Visit the IRS EIN Assistant
Go to irs.gov and navigate to the EIN Assistant. This is the only official, free way to apply for an EIN online. You don't need to create an account or log in.
2. Select your entity type
Choose the structure that matches your state filing: sole proprietor, LLC, corporation, partnership, non-profit, or estate/trust. If you're unsure, refer to your formation documents. Selecting the wrong type is one of the most common application errors.
3. Enter your business information
Provide your legal business name, physical address, and responsible party details. The responsible party is the individual who controls, manages, or directs the entity and its funds. Their name and SSN or ITIN must match what's on file with the Social Security Administration exactly.
4. Confirm your details
Review all information before submitting. The IRS doesn't allow corrections through the online system after submission. If you spot an error, you'll need to call the IRS Business & Specialty Tax Line to make changes.
5. Receive your EIN immediately
Once you submit, the IRS issues your EIN on the spot. Save or print your CP-575 confirmation notice immediately. This is your official record and proof of your EIN assignment. The IRS won't send a duplicate online, so don't close the browser until you've saved it.
Common EIN application mistakes
These are the most frequent errors that delay or complicate the EIN process.
Applying for multiple EINs
You only need one EIN per entity. If you operate multiple businesses under the same LLC or corporation, they all share one EIN. Applying for a second creates confusion with the IRS and can trigger compliance questions.
Entering incorrect responsible party info
The responsible party's name and SSN must match exactly what's on file with the Social Security Administration. Even small discrepancies, like a middle initial vs. a full middle name, can cause the application to be rejected.
Selecting the wrong entity type
This is especially common with LLCs. A single-member LLC is not the same as a sole proprietorship for EIN purposes. Choose the entity type that matches your state formation documents, not how you intend to be taxed.
Not saving your confirmation
The IRS issues your EIN once and displays your CP-575 notice on screen. If you close the window without saving, you'll need to call the IRS or wait for a mailed copy. Save it as a PDF or print it before navigating away.
Paying a third-party service
EIN applications are always free through the IRS. Any website charging a fee is a third-party filing service doing exactly what you can do yourself in 5 minutes. There's no advantage to paying for something the government provides at no cost.
How to get an EIN by mail, fax, or phone
If you can't apply online, the IRS offers alternative methods at no cost.
Apply by mail
Complete Form SS-4 and mail it to the IRS. Processing takes 4–6 weeks. If you're a domestic applicant, mail your application to:
Internal Revenue Service Attn: EIN Operation Cincinnati, OH 45999
If you're applying from outside the US, send your application to:
Internal Revenue Service Attn: EIN International Operation Cincinnati, OH 45999 USA
Apply by fax
You can fax Form SS-4 and receive your EIN within about 4 business days. The fax number depends on your location:
- Domestic applicants (US entities): 855-641-6935
- International applicants (outside the US): 1-304-707-9471
- International applicants filing from inside the US: 855-215-1627
Make sure you include a return fax number so the IRS can send your EIN back to you.
Apply by phone
International applicants can call the IRS directly at 1-267-941-1099 to apply for an EIN over the phone. The line is open weekdays from 6am to 11pm Eastern time. This is the only option for applicants located outside the US who don't have an SSN or ITIN.
| Method | Processing time | Best for |
|---|---|---|
| Online | Immediate | US-based applicants with SSN/ITIN |
| Fax | About 4 business days | Those without internet access |
| 4–6 weeks | Non-urgent applications | |
| Phone | Same day | International applicants |
When you need a new EIN
Certain business changes require you to apply for a new EIN:
- Change in business structure: You transition from a sole proprietorship to an LLC, or from an LLC to a corporation
- New ownership: You purchase or inherit an existing business
- Incorporation: You form a new partnership or bring new partners into an existing one
- Bankruptcy: Certain bankruptcy proceedings require a new EIN
You don't need a new EIN if you operate multiple businesses under the same entity, change your business name, or relocate your company.
How to look up your EIN
If you've lost or forgotten your EIN, there are several ways to track it down:
- Check previous tax returns: Your EIN appears on every filed business return
- Review bank records: Your EIN is on your business account paperwork and opening documents
- Contact the IRS: Call the Business & Specialty Tax Line at 800-829-4933 to request your EIN
- Check IRS notices: Any correspondence you've received from the IRS includes your EIN
The IRS Business & Specialty Tax Line is available Mon–Fri, 7am–7pm local time. Have your business information ready, as the agent will need to verify your identity before releasing the number.
Your CP-575 confirmation letter is your primary official record. If you saved it when you originally applied, check there first. It's the fastest way to confirm your number without waiting on hold.
One important detail: An EIN never expires. Even if you close a business, the IRS never reuses or reassigns the number. If you're reopening an old entity, you can use the original EIN.
Apply for the Ramp Corporate Card using only your EIN
An EIN lets you separate your business and personal finances cleanly. One of the simplest ways to do that is to apply for a business card that doesn't require a personal guarantee or credit check.
The Ramp Corporate Card only requires your EIN and at least $25,000 in a US business bank account. Once you apply, you can get approved in under 48 hours, with no hard pull on your personal credit.
Beyond simplified approval, Ramp includes built-in expense management tools that help you reduce spending. Set transaction limits by vendor or category, issue unlimited physical and virtual cards for your team, and submit receipts instantly through SMS, mobile app, or integrations such as Gmail and Amazon. You also get real-time spend visibility and automated expense categorization that simplifies tax time.
Ready to get started? Try an interactive demo to see how Ramp helps you manage spending from day one.
FAQs
The fastest way is through the IRS EIN Assistant online at irs.gov. The application takes about 5 minutes and you receive your EIN immediately. It's available Mon–Fri, 7am–10pm ET.
No. Applying for an EIN is completely free through the IRS, regardless of which method you use (online, fax, mail, or phone). Any website charging a fee for EIN applications is a third-party service you don't need.
Form your LLC first, then apply for an EIN. The IRS requires your entity type and legal business name during the EIN application, so your business must be registered with your state before you can get an EIN.
Single-member LLCs without employees aren't legally required to have an EIN, but most apply for one anyway. An EIN simplifies business banking, helps build business credit, and protects your personal Social Security number.
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