How to apply for an Employer Identification Number using Form SS-4

• An Employer Identification Number (EIN) is a unique nine-digit number that the Internal Revenue Service (IRS) assigns to businesses for tax purposes.
• Most business structures, including corporations, partnerships, and LLCs with employees, need an EIN to file tax returns, hire employees, and open a business bank account.
• You can apply for an EIN online for free through the IRS website and receive it instantly.
• You can also submit your application by mail or fax using Form SS-4, which may take several weeks to process.
• If you choose to mail or fax your application, you can use a tool like pdfFiller to easily complete and file your Form SS-4, ensuring all information is accurate and legible.

Starting a new business involves many steps, but one of the most critical is getting a federal tax ID. To get one, you’ll need to apply for an Employer Identification Number (EIN) with the IRS using Form SS-4, Application for Employer Identification Number. This form gives your business a unique identifier for tax filing and reporting.

Understanding how to correctly fill out and submit Form SS-4 is crucial for maintaining compliance and managing your small business taxes. This guide will walk you through everything you need to know about the EIN application process.

What is an EIN, and who needs one?

An Employer Identification Number (EIN) is a unique nine-digit number assigned by the IRS to business entities operating in the United States. Think of it as your business tax ID used instead of a personal taxpayer identification number. Its primary purpose is for tax reporting. The IRS uses this number to track a business’s tax filings and payments, including employment taxes and income tax returns.

According to the official IRS instructions, you typically need an EIN if:

• You have employees expected (or already on payroll).
• You operate as a corporation, partnership, or limited liability company (even if you’re a single-member LLC for tax purposes).
• Your business files employment taxes, excise taxes, or other federal business tax returns.
• You open business bank accounts or a business account with payment processors.
• Your business structure includes a trust, estate, non-profit organization, government entity, or other entities that need a separate tax ID.
• You’re applying for certain business licenses or permits that require a federal tax ID.

Even if the IRS does not strictly require an EIN for your business type, getting one is often a critical step. It allows you to separate your personal finances from your business activities, which simplifies accounting and protects your personal assets.

When do you need an EIN vs. when can you use an SSN?

A common question among sole proprietors and freelancers is: “Do I need an EIN or can I use my SSN?” Deciding between an EIN and your personal SSN can be confusing for new business owners. The choice depends on your business structure and activities.

You can use your SSN for business purposes if you’re a sole proprietor without employees, since your personal and business taxes are filed together. Many freelancers and independent contractors operate this way. However, you’ll need an EIN if you hire employees (even a single one), change your business structure to an LLC or corporation, or need to file excise or specific tax returns.

You need an EIN if:

• You hire employees or report wages. 
• You operate as a partnership, corporation, or multi-member LLC. 
• You file employment, excise, or certain information taxes. 
• You file business tax returns separately from personal taxes. 
• A bank or lender requires a tax ID for an account or credit. 
• You’re a non-resident alien or foreign business needing a taxpayer ID for US taxes.

Even if the IRS doesn’t require you to get an EIN, many sole proprietors still choose to apply. Having an EIN makes it easier to separate personal and business finances, protect your Social Security Number on official documents from potential identity theft risks, and prepare for future growth, such as hiring employees or changing your business structure.

Refer to the IRS guidelines on Form SS-4, page 2, to determine who is required to apply for an EIN.

How to apply for an EIN online

The fastest and easiest way to obtain an EIN is to apply online through the official IRS website. Ensure you gather all the information in advance.

Here is a step-by-step guide to the online application:

1. Visit the IRS website and navigate to the official EIN application page. Never use third-party websites that charge fees for this service. The official IRS site clearly states that it provides a free EIN application process.
2. Determine eligibility: You can apply online if your principal business is in the U.S. or its territories. The responsible party must have a valid Taxpayer Identification Number (SSN, ITIN, or EIN). Ensure you meet these conditions before starting.
3. Begin the application: Read the guidelines and click Begin Application Now. The system times out after 15 minutes of inactivity, so gather all necessary details beforehand.
4. Complete your application: Select our entity type, provide business details, reasons for applying, the responsible party’s information, and answer questions about your business activities.
5. Review and submit: Carefully check your answers. Once you submit the completed form, your application will be validated.
6. Receive your EIN: After successful validation, you will receive your EIN immediately. Download, save, and print your EIN confirmation letter for your records.

Form SS-4 paper application instructions

If you prefer not to apply online or are ineligible to do so, you can apply for an EIN by mailing or faxing Form SS-4 to the IRS. This method is also common for international applicants.

Using a tool like pdfFiller can simplify this process. You can easily find the current fillable Form SS-4 in pdfFiller form library and instantly upload it to the editor. pdfFiller’s tools allow you to type directly onto the form, ensuring your information is neat and legible. 

Here are the instructions:

1. Log in to pdfFiller or create an account and start a 30-day free trial.

2. Obtain the form: Upload the Form SS-4 downloaded from the IRS website or click Add new > Search PDF Library > Forms & Applications, find the latest SS-4 template, and click Fill online to upload it to the editor.

3. Complete the form fields. Start on Line 1 and click Next to move through the form—the editor will guide you so you don’t miss any required fields. Provide the following information:

• Lines 1-6: Business name, trade name (if any), mailing address, and physical location.
• Line 7a-7b: The name of the responsible party and their SSN, ITIN, or EIN.
• Line 8a-8c: Specify if the application is for an LLC or a foreign equivalent, enter the number of LLC members, and indicate if it’s organized in the U.S.
• Line 9a: Check the corresponding box to indicate your type of entity.
• Line 10: Choose the reason for applying (e.g., starting a new business, hiring employees).
• Easily fill out Form SS-4 online in the pdfFiller editor.
• Line 11: Enter the date when your business started or was acquired.
• Line 12: The closing month of your accounting year.
• Line 13: The highest number of employees expected in the next 12 months.
• Line 15: First date wages or annuities paid.
• Line 16: Check one box to describe your business activity.
• Line 17: Indicate the principal line of merchandise sold, specific construction work done, products produced, or services provided.
• Line 18: Check if the entity from Line 1 ever applied for or received an EIN.

4. Third-Party Designee section. Fill out this section only if you wish to authorize someone to receive the entity’s EIN and address questions about this form. Enter your and your designee’s phone and fax numbers.

After you complete and review the document, save changes and print the form. Then, sign and date your application and send it to the IRS.

How do I file my paper Form SS-4?

The official IRS instructions list the correct fax numbers and mailing addresses for filing Form SS-4, organized by business location.

Where To File or Fax

International applicants can apply for an EIN by calling 267-941-1099. This non-toll-free line is available Monday to Friday, 6:00 a.m. to 11:00 p.m. Eastern Time, for those without a legal residence, business, or office in the U.S. or its territories.

How long does it take to get an EIN?

The time it takes to receive your EIN depends on the application method you choose.

• Online application: You get your EIN immediately once the application is approved.
• Fax: You can typically expect your EIN in about four business days, assuming all information is correct.
• Mail: Processing can take up to four weeks or longer.
• Telephone (International applicants only): Obtaining an EIN by phone can be instantaneous, but hold times vary. The IRS then sends written confirmation.

The IRS EIN confirmation letter is your official documentation; store it securely with your business records. You’ll need it to open bank accounts, apply for licenses, and file taxes.

Different entity types and EIN requirements

The requirement for an EIN often depends on your business structure, or entity type. Each structure has its own unique rules and tax implications.

• Sole proprietorship: You are not required to get an EIN and can use your SSN if you are a sole proprietor with no employees. However, you must get an EIN if you hire employees, file for bankruptcy, or purchase a business.
• Partnership: All partnerships need an EIN for tax filing and reporting purposes, regardless of whether they have employees.
• Corporation: All corporations (including S-corporations and C-corporations) must have an EIN. This is true even if the corporation has no employees.
• Limited Liability Company (LLC): The rules for an LLC depend on its tax structure. A single-member LLC without employees can use the owner’s SSN and doesn’t need an EIN. However, it must get an EIN if it has employees or chooses to be taxed as a corporation. All multi-member LLCs must obtain an EIN.
• Other entities: Estates, trusts, and non-profit organizations also need an EIN for tax reporting.

What to do if you lose your EIN

Losing your EIN is common, but you can retrieve it. Here are some steps to take:

• Search for documents that display your EIN (previous tax returns, bank account documents, payroll records, or official letters from the IRS).
• Call the IRS: Contact the IRS Business and Specialty Tax Line at 800-829-4933. Representatives are available Monday through Friday from 7:00 a.m. to 7:00 p.m. Eastern Time. They will verify your identity and authority to receive the EIN before providing it over the phone.

Final thoughts

Obtaining an EIN is a crucial step for ensuring tax compliance and operating your business effectively. The IRS provides several application methods, including a free online application on their website, submitting Form SS-4 by mail or fax, or applying by phone for international applicants.

The application process requires accuracy and attention to detail. With pdfFiller, you can easily access and fill out Form SS-4, type in your information to avoid errors from messy handwriting, and save a digital copy for your records. This simplifies the preparation process, so you can get back to what matters most—running your business.

Ready to complete your EIN application? Start a free trial with pdfFiller to fill out your Form SS-4 today!

Glossary

• Employer Identification Number (EIN): A nine-digit number uniquely assigned by the IRS to identify business entities for tax purposes.
• Responsible party: An individual who has ultimate ownership or control over the business entity applying for the EIN (their name and Taxpayer Identification Number must be included on the Form SS-4).
• Sole proprietorship: A business owned and operated by one person, with no separation between the owner and the business. The owner keeps all profits but is also responsible for all debts, losses, and liabilities.
• Limited Liability Company (LLC): A business structure in the U.S. that protects its owners from personal responsibility for its debts or liabilities, combining the characteristics of a corporation with those of a partnership or sole proprietorship.