Businesses need to understand the differences between an Employer Identification Number (EIN), Social Security Number (SSN), and Individual Taxpayer Identification Number (ITIN) in order to remain tax compliant. These unique identifiers serve a distinct purpose, from identifying business entities to tracking personal earnings and years employed. 

In this guide, we will take a look at the specific roles and requirements of an ITIN vs EIN vs SSN, providing clarity on their usage, application processes, and security considerations to ensure you file taxes accurately and protect sensitive financial information.

EIN vs. ITIN vs. SSN: What they are and how to get them

For each of these tax identifiers, there are different definitions and different ways to apply for them. Let’s take a closer look below. 

What is an EIN?

An EIN is used to identify a business entity for tax purposes and to separate the business from its owner. Businesses, such as corporations, partnerships, and LLCs with employees, need an EIN so that they can file tax returns separately from their owners. This is what enables business owners to keep their personal and business finances separate and protect sensitive information. 

An EIN is also used during the application process for business loans and business bank accounts. If you run a business and need to retrieve your EIN, then you can use an EIN lookup service online too. 

How to obtain an EIN

To get an EIN online, visit the IRS website, as the best application method is online. Once you’ve gotten to the portal, click on “Apply Online Now” under the “Apply for an EIN” section, and select the reason for applying. Choose whether you are applying as an individual or a business, enter your personal information, and select the type of business you are starting. Briefly describe your business and choose how you would like to receive your EIN. Review your information and apply. If applying online, you will receive your EIN immediately.

What is an ITIN?

An ITIN is used to identify individuals who are not eligible for an SSN, such as nonresident aliens, and undocumented aliens. It is used for tax purposes but does not authorize the holder to work in the U.S. This permission is granted by a separate document. However, if someone with ITIN eligibility works in the U.S, then this is the number the IRS will use to identify that individual when it comes to filing taxes. 

How to obtain an ITIN

An ITIN is obtained from the IRS by filling out Form W-7. After you have correctly completed all of this information, you can submit it with your tax return, which is the most common method. Alternatively, you can contact an IRS-authorized Certifying Acceptance Agent (CAA) to help you complete and submit the application, or make an appointment with the IRS Taxpayer Assistance Center (TAC) to apply in person. 

CAAs are required to meet specific requirements, including having a valid Employer Identification Number (EIN), being an established Volunteer Income Tax Assistance (VITA) or Tax Counseling for the Elderly (TCE) site, and passing a tax compliance check. They must also complete mandatory training and adhere to specific standards and procedures to ensure the integrity of the ITIN application process. There are also options to email your application to the IRS or post it using the specified information on the form. 

When applying, you will need to provide supporting documents, such as a valid passport, I-94 arrival record, and I-20 or DS-2019, depending on your situation. Ensure your application is complete and accurate to avoid delays or denials. Be aware that ITIN applications can take up to nine months to process, with no approval guarantee.

What is an SSN?

A Social Security Number (SSN) is a nine-digit number assigned by the Social Security Administration (SSA) to track U.S. citizens, permanent residents, and temporary residents (like students or contract workers) for tax and wage reporting purposes. It is used to identify individuals on tax forms and is required for various activities such as:

  • Opening a bank account
  • Applying for credit cards
  • Filing taxes
  • Receiving Social Security benefits
  • Applying for student loans
  • Obtaining a driver’s license (in some states)

How to obtain an SSN

Your application for an SSN depends on the capacity in which you’re applying for one. In most cases, you will be required to fill out an SS-5 form which will grant you a Social Security Card if approved. 

To obtain an SSN as a student or international worker you can do the following. For F-1 and J-1 students, you can complete an online form and select the required documents, including a valid passport, I-20, and I-94. Alternatively, you can make an appointment by calling 1-800-772-1213 or your local social security office number and bring the necessary documentation. 

For F-1 and J-1 students with employment authorization, it’s also possible to visit the SSA office with the Employment Authorization Document (Form I-766) and proof of age (birth certificate or foreign passport). Again, it’s essential to bring the required documents, including the Form I-766 and birth certificate. The SSA will verify your immigration status and issue your SSN card within 2 weeks after your application. Ensure your Student and Exchange Visitor Information System (SEVIS) record is in Active status for at least 2 days before applying and wait at least 10 days after arriving in the United States before applying.

When applying for an SSN, you always need to take original documents to prove age, identity, and work-authorized immigration status. Any SSA office will allow you to apply in person. If you are unable to apply in person, you can delay your application until you are in the United States and can apply at a local SSA office. Make sure you have all the necessary documents before applying and bring photocopies of your documents to expedite the process.

EIN vs ITIN vs SSN: The key differences

Although the nature, purpose and application processes are very different for each of these identifiers, you will still need to understand some more of the other differences, especially if you run a business or have to file tax. 


EINs and SSNs fundamentally differ in their issuance, purpose, usage, requirement, application process, and uniqueness. An EIN is issued by the Internal Revenue Service (IRS) to identify businesses for tax purposes, whereas an SSN is issued by the Social Security Administration (SSA) for employment and Social Security benefits.

The purpose of an EIN is to track and verify a company’s tax reporting and payments, whereas an SSN is used for employment, credit, and other purposes pertaining to citizenship. EINs are required for businesses that pay employees or are required to file tax returns, whereas SSNs are required for individuals who work as employees in the US. The application process for an EIN can be completed online, by fax, mail, or phone, whereas the application process for an SSN involves filling out a form and submitting it to the SSA, along with required documents.

Each business entity has a unique EIN, whereas each individual has a unique SSN, making them different in purpose. 


An EIN is used to identify a business entity for tax purposes and to separate the business from its owner. It is issued to businesses operating in the United States and is available to all business entities, including corporations, LLCs, partnerships, non-profits, estates, and trusts. The EIN is a nine-digit number in the format XX-XXXXXXX and is used by businesses to open bank accounts, apply for loans, handle payroll, and file taxes.

An ITIN, on the other hand, is used by individuals who are not eligible for an SSN to file tax returns and conduct other tax-related activities. It is issued by the IRS to individuals, regardless of their immigration status, who have a U.S. tax filing or reporting requirement. The ITIN is a nine-digit number always starting with the digit “9” and formatted like an SSN: 9XX-XX-XXXX. It is available to individuals such as nonresident aliens, resident aliens, their spouses, and dependents.

An EIN is a business tax ID number, while an ITIN is a personal tax ID number for individuals who are not eligible for an SSN. Both are important for tax compliance purposes but serve different business and individual functions.


An SSN is a general identification number used by U.S. citizens and authorized residents for employment, Social Security benefits, and other purposes, while an ITIN is specifically used for tax purposes by individuals who are not eligible for an SSN, such as nonresident aliens, resident aliens, their spouses, and dependents.

With an SSN, you can work legally in the U.S., collect Social Security benefits, and access various financial and medical services, while an ITIN does not provide legal immigration status or work authorization. However, an ITIN can be used to file tax returns, open bank accounts, and obtain driver’s licenses in selected states when you are working in the U.S.


Let’s sum it up and break it down. An EIN is used to identify businesses for tax purposes, issued by the IRS, and required for businesses to open corporate bank accounts, apply for loans, and file taxes. 

An ITIN is used for tax purposes by individuals who are not eligible for an SSN, issued by the IRS, and required for non-resident aliens, resident aliens, their spouses, and dependents who need to file U.S. tax returns. 

An SSN is used for employment and Social Security benefits, issued by the Social Security Administration (SSA), and required for U.S. citizens and authorized permanent residents. 

Hopefully this makes it slightly easier for you to understand the different tax and identity numbers issues by US authorities. For more help or to find a misplaced EIN, simply log on to, and we’d be happy to help.