What is Form SS-4?

Form SS-4 (Application for Employer Identification Number) is the official IRS form used to apply for an Employer Identification Number (EIN). An EIN is a unique nine-digit number assigned to business entities by the IRS for identification purposes. Even if your business has no employees, you may need an EIN for tax filing, banking, and business operations. The EIN functions similarly to a Social Security Number, but for your business rather than an individual.

Whether you're starting an LLC, corporation, partnership, sole proprietorship with employees, or nonprofit organization, Form SS-4 is the standard application for obtaining your unique identifier.

Who Needs to Apply for an EIN?

You Must File Form SS-4 If You:

Operate a partnership or corporation
Formed an LLC with two or more members
Plan to hire employees
Have a Keogh plan (self-employed retirement plan)
Operate a nonprofit organization or educational institution
File excise tax returns
Established an employee pension plan
Operate a farm with seasonal employees
Own a business that requires federal licenses
Need an EIN for banking purposes (even without employees)
Changed your business structure (e.g., incorporated a sole proprietorship)

You May Not Need an EIN If You:

Are a sole proprietor with no employees (can use SSN instead)
Only collect sales tax (verify with your state)
Operate as a sole proprietor and don't plan to hire anyone
But note: Many businesses find it beneficial to obtain an EIN even without these requirements

What Information Do You Need?

Personal/Business Information Required:

Your full legal name (individual or business entity)
Mailing address
Business address (if different from mailing)
Phone number
Your Social Security Number (if applying individually)
Date you expect to start or have started your business
Your current occupation
Country of citizenship (if applicable)

Business Structure Information:

Type of business entity (sole proprietor, partnership, corporation, LLC, etc.)
Date the business structure was established or incorporated
Business name exactly as it appears on legal documents
Principal line of business (e.g., management consulting, retail, manufacturing)
State of formation or incorporation
Federal income tax return filing status or exemption status

Employment and Payroll Information:

Whether you expect to hire employees
Estimated number of employees
Anticipated first payroll date
If you're taking over an existing business, previous EIN (if available)

Banking and Financial Information:

Estimated monthly payroll amount (if applicable)
Type of income reported (wages, dividends, royalties, rental income)
Any existing business accounts or licenses

Step-by-Step Instructions

Online Application (Recommended - Fastest):

1. Prepare Your Information

Gather all required business and personal information
Ensure you have a valid Responsible Party SSN
Have your business structure documents ready (Articles of Incorporation, LLC Operating Agreement, etc.)

2. Visit the IRS EIN Online Application

Go to IRS.gov and search "Apply for an EIN Online"
Access the online application portal
Confirm you meet eligibility requirements
Begin the application process

3. Complete the Online Form

Answer questions about your business structure
Provide legal entity information
Enter responsible party information (typically owner or manager)
Specify your principal business activity
List employment and payroll details if applicable
Review all information for accuracy

4. Receive Your EIN Immediately

Upon successful completion, your EIN appears on screen immediately
Print the confirmation page
The IRS sends a confirmation letter by mail within 15 days
You can begin using the EIN immediately

5. Save Your Documentation

Print the confirmation page with your EIN
Save a digital copy to your files
Store safely for business records
Use for banking, tax filing, and business licensing

Paper Application (Form SS-4):

1. Obtain the Form

Download Form SS-4 from IRS.gov
Print or request by mail
Have instructions readily available

2. Complete the Form

Fill out your name and address (lines 1-5)
Enter business name and address (lines 6-7)
Select appropriate business type (lines 11-12)
Specify your principal business activity (line 11)
Enter estimated payroll and employment details (lines 13-15)
Sign and date the form (line 17)

3. Mail to the IRS

Send to the IRS address listed in instructions (varies by state)
Allow 4-6 weeks for processing by mail
Include a cover letter explaining your business
Consider certified mail for tracking

4. Wait for Confirmation

IRS mails a confirmation letter within 15 days
The letter contains your assigned EIN
Keep this letter as your official EIN documentation
You can reference the EIN before receiving the official letter if needed

5. Update Business Records

Record your EIN in business accounting systems
Provide to banks for business account setup
Include on business licenses and filings
Communicate to employees and vendors as needed

Phone Application (If Eligible):

1. Call the IRS Business Line

Phone: 1-800-829-4933
Hours: Monday-Friday, 7 AM to 10 PM local time
Have all required information available
Be ready to verify your identity

2. Provide Information to Representative

Verify your identity and responsible party status
Answer questions about your business
Confirm EIN assignment details
Receive confirmation number

3. Receive Written Confirmation

IRS mails official confirmation letter
Arrives within 15 days of application
Contains your assigned EIN
Keep with business records

Processing Times by Method

Application Method	Processing Time	When You Can Use EIN
Online (IRS.gov)	Immediately	Same day
Phone (800-829-4933)	Immediate over phone	Same day
Fax/Mail	4-6 weeks	After confirmation letter received
Paper Mail	4-6 weeks	After confirmation letter received

Common Mistakes to Avoid

Wrong Business Structure: Double-check whether you're truly a partnership, LLC, or sole proprietor before applying
Incorrect Legal Name: Use the exact legal name as it appears on business documents, not a nickname or doing-business-as (DBA) name
Incomplete Information: Missing responsible party information or principal business activity delays processing
Wrong EIN Reason Code: Select the correct reason for applying to ensure proper classification
Failure to Update Changed Information: If your business structure changes, you may need a new EIN
Assuming You Don't Need One: Many sole proprietors could benefit from an EIN even without employees

After You Receive Your EIN

Important Next Steps:

Open a business bank account using your EIN
Obtain necessary business licenses and permits
Register with state tax authorities (sales tax, payroll tax, etc.)
Set up payroll systems if you have employees
Begin record-keeping for business income and expenses
Register for federal tax return filing (Form 1120, 1065, Schedule C, etc.)
Notify insurance companies of your business structure
File required annual reports or tax returns

Frequently Asked Questions

Q: How long does it take to get an EIN? A: Online applications receive an EIN immediately. Phone applications receive confirmation over the phone same day. Paper applications take 4-6 weeks. An IRS confirmation letter arrives within 15 days for online/phone and is part of the paper process.

Q: Can I apply for an EIN if my business isn't formed yet? A: Yes, you can apply up to several weeks before your business begins operations. Specify your anticipated start date on the application.

Q: Do I need an EIN as a sole proprietor? A: Not required if you have no employees. However, many sole proprietors obtain one to keep their SSN private and establish business credibility with banks and vendors.

Q: Can I have multiple EINs? A: One business entity should have only one EIN. If you have multiple separate business entities, each gets its own EIN.

Q: What if I made a mistake on my application? A: Contact the IRS at 1-800-829-4933 to request corrections. For significant errors, you may need to apply again with corrected information.

Q: Do I need to reapply if my business address changes? A: No, your EIN remains the same. Notify the IRS of address changes using Form 8822-B (Change of Address).

Q: How do I find my EIN if I lost it? A: Check your IRS confirmation letter, prior tax returns, business bank statements, or call the IRS at 1-800-829-4933 with business information.

Q: Is there a fee to apply for an EIN? A: No, there is no charge to apply for an EIN. Be wary of third-party services charging fees for EIN applications.

Q: Can I apply for an EIN online if I'm outside the United States? A: Foreign applicants may need to apply by phone or paper. Contact the IRS for guidance on your specific situation.

Q: What's a Responsible Party on a Form SS-4? A: The responsible party is the individual who has legal authority over the business entity (owner, member, partner, officer). This person must have a valid U.S. SSN or ITIN.

Q: How soon can I use my EIN after receiving it? A: You can begin using your EIN immediately upon receiving it (either online, by phone, or when you receive the confirmation letter from paper applications).

Q: Do nonprofits and charitable organizations need an EIN? A: Yes, if applying for tax-exempt status or operating as a corporation, partnership, or LLC. Form SS-4 is used for initial EIN; Form 1023 or 1023-EZ is used for tax-exempt status.

IRS Form SS-4: Application for Employer Identification Number