Gokce Tandogdu
ITIN Specialist, itin.net
You cannot combine an ITIN and an SSN because they serve different purposes and are issued by the IRS under different eligibility criteria. An Individual Taxpayer Identification Number (ITIN) is issued to individuals who need a U.S. taxpayer identification number but do not have and are not eligible to obtain a Social Security Number (SSN). An SSN is issued by the Social Security Administration (SSA) to U.S. citizens, permanent residents, and temporary (working) residents. If you are eligible for an SSN, obtaining one will supersede your ITIN for all U.S. tax filing and identification purposes. This answer addresses the core question of how to combine ITIN and SSN by explaining their distinct nature and the process for obtaining an SSN if you become eligible.
Understanding the Difference Between ITIN and SSN
The fundamental distinction lies in eligibility and issuing authority. The IRS issues ITINs primarily to foreign nationals for U.S. tax purposes, such as filing federal tax returns, claiming tax treaty benefits, or meeting U.S. tax law requirements. Eligibility for an ITIN is generally tied to a U.S. tax filing obligation or a specific tax-related reason. For example, if you are a non-resident alien who needs to file a U.S. tax return but cannot get an SSN, you must apply for an ITIN using Form W-7, Application for IRS Individual Taxpayer Identification Number.
An SSN, on the other hand, is issued by the Social Security Administration (SSA) and is primarily for tracking an individual's lifetime earnings and determining eligibility for Social Security benefits. It is also used by employers for wage reporting and tax withholding. Eligibility for an SSN is typically granted to U.S. citizens, lawful permanent residents (green card holders), and individuals with specific work authorizations from the U.S. Department of Homeland Security.
Therefore, the concept of "combining" an ITIN and an SSN is not applicable. They are mutually exclusive in terms of issuance and primary function. If you hold an ITIN and later become eligible for an SSN, you will use the SSN for all future tax filings. The IRS will associate both numbers with your record, but the SSN will be the primary identifier for tax purposes once issued.
Eligibility for an SSN
Becoming eligible for an SSN is the only pathway to effectively "replace" your ITIN with a Social Security Number. Eligibility is strictly defined by the SSA and generally includes:
- U.S. Citizens: Born in the U.S. or naturalized citizens.
- Lawful Permanent Residents: Individuals holding a green card.
- Non-Resident Aliens Authorized to Work in the U.S.: This is a crucial category for many individuals who might currently hold an ITIN. Authorization typically comes in the form of an Employment Authorization Document (EAD) issued by USCIS (Form I-766), or specific visa statuses that permit employment, such as certain H-1B, L-1, or O-1 visas.
If you are a foreign national working in the U.S. for a U.S. employer, or operating a U.S. business that requires you to be present and authorized to work, you will likely apply for an SSN. The process involves obtaining the necessary work authorization documentation first. Without authorization to work in the U.S. from the SSA's perspective, you will not be eligible for an SSN, and an ITIN will remain your required taxpayer identification number for U.S. tax obligations.
When an SSN Supersedes an ITIN
Once you are issued an SSN by the Social Security Administration, it becomes your primary identification number for all U.S. tax and employment purposes. If you have previously applied for and received an ITIN, you must use your SSN for all tax filings going forward. The IRS system will recognize the SSN as your primary identifier.
For example, if you filed your 2022 U.S. federal tax return using an ITIN, and you receive an SSN in 2023, you must file your 2023 tax return using your SSN. You should also inform the IRS of your new SSN. While there isn't a specific form solely for updating your SSN to replace an ITIN, the most common way to notify the IRS is by filing Form W-4, Employee's Withholding Certificate, with your employer, which includes a field for your SSN. This action, combined with future tax filings using your SSN, will update your record with the IRS.
It is important to note that your ITIN does not become invalid. It remains associated with your tax history. However, for all new tax filings and official U.S. government interactions requiring a taxpayer identification number, the SSN is the one you must use. This is why the question of "how to combine ITIN and SSN" is better framed as "how to transition from an ITIN to an SSN" once eligible.
Applying for an SSN
The application process for an SSN is managed by the Social Security Administration (SSA), not the IRS. The primary form used is Form SS-5, Application for a Social Security card. You will need to apply in person at an SSA office, although some exceptions may apply for those overseas.
To apply for an SSN, you generally need to provide proof of:
- Identity: A valid, unexpired government-issued identification document such as a U.S. driver's license, state-issued ID card, or passport.
- Age: A birth certificate or passport showing your date of birth.
- Immigration Status and Work Authorization: This is the critical piece for foreign nationals. You will need documentation from the Department of Homeland Security (DHS) that shows you are authorized to work in the U.S. This could be an EAD, an approval notice for a work-authorized visa, or other relevant immigration documents.
The process typically looks like this:
- Obtain Work Authorization: If you don't already have it, secure the necessary documentation from DHS that grants you permission to work in the U.S.
- Gather Required Documents: Collect your proof of identity, age, and work authorization. Ensure all documents are original or certified copies.
- Complete Form SS-5: Fill out the application form accurately and completely. You can download it from the SSA website (ssa.gov).
- Visit an SSA Office: Schedule an appointment or visit your local Social Security office with your completed form and original supporting documents.
- Receive Your SSN Card: If approved, the SSA will mail your Social Security card with your new SSN to the address you provided. Processing times can vary but often take a few weeks.
If you are applying for an SSN because you are an employee of a U.S. company, your employer will likely guide you through this process and will need your SSN for payroll and tax withholding purposes.
What If You Are Not Eligible for an SSN?
Many foreign nationals residing outside the U.S., or in the U.S. in a non-work-authorized status, will not be eligible for an SSN. In such cases, the ITIN remains the necessary taxpayer identification number for any U.S. tax obligations. Common scenarios where an ITIN is required and an SSN is not obtainable include:
- Non-resident aliens who receive U.S. source income (e.g., rental income from U.S. property, dividends from U.S. stocks) and need to file a U.S. tax return to report this income or claim treaty benefits.
- Dependents or spouses of U.S. citizens or resident aliens who are non-resident aliens themselves and file a U.S. tax return.
- Individuals who are required to file Form 5472 to report transactions with a U.S. LLC where they are the sole member, and the LLC is treated as a disregarded entity for U.S. tax purposes. This often applies to foreign owners of U.S. businesses. Establishing a U.S. LLC is a common step for foreign nationals investing in the U.S., and subsequent tax filings may necessitate an ITIN.
- Opening a U.S. bank account where an ITIN is accepted as a valid identification number. While many banks require an SSN, some institutions, particularly those catering to international clients or fintech companies like Mercury, Relay, or Brex, may accept an ITIN. Opening a U.S. bank account is often a precursor to other business activities.
If you are in one of these situations, you will need to apply for an ITIN using Form W-7. The application process for an ITIN can be done by mail directly to the IRS, through an Acceptance Agent, or by visiting an IRS Taxpayer Assistance Center (TAC) by appointment. itin.net provides a streamlined service to assist eligible individuals in obtaining their ITINs. Applying through a Certified Acceptance Agent, or CAA, is often a convenient option as they can help verify your original identification documents, reducing the need to mail them to the IRS.
ITIN Renewal and SSN Eligibility
ITINs are subject to renewal. The IRS requires ITINs that have not been used on a federal tax return for three consecutive filing years to be renewed. Additionally, the IRS has a policy of expiring ITINs in phases based on the middle digits. If your ITIN expires, and you still have a U.S. tax filing requirement but are not eligible for an SSN, you must renew your ITIN by submitting Form W-7 again, along with supporting documentation.
If, during the period your ITIN is valid or when you need to renew it, your circumstances change and you become eligible for an SSN (e.g., you obtain work authorization), you should apply for the SSN immediately. Once you have your SSN, you will use it for all future tax filings. You do not need to wait for your ITIN to expire. The IRS system will update your primary taxpayer identification number to your SSN once it is issued and used in tax filings.
Important Considerations
- Never Lie on Applications: Always provide accurate information on Form W-7, Form SS-5, or any other government forms. Misrepresenting your eligibility for an SSN or ITIN can lead to severe penalties.
- SSN is Prioritized: If you are eligible for and obtain an SSN, it automatically takes precedence over any ITIN you may have been issued previously. You must use the SSN for all tax-related matters going forward.
- Consult Professionals: The U.S. tax and immigration systems are complex. If you are unsure about your eligibility for an SSN, the process of applying for either an SSN or an ITIN, or your U.S. tax obligations, it is highly recommended to consult with a qualified tax professional or immigration attorney. For guidance on ITIN applications, the specialists at itin.net are available to help.
In summary, the question of "how to combine ITIN and SSN" is resolved by understanding that they are separate numbers. The pathway is not combination, but transition: obtain an SSN if you become eligible, and use that as your primary tax identification number. If SSN eligibility is not met, the ITIN remains essential for fulfilling U.S. tax responsibilities.