If you are a non-US citizen earning money from the United States, you likely have a tax obligation. To fulfill that obligation, you need a specific tax ID number.
While US citizens use Social Security Numbers (SSN), international founders cannot get one of those. Instead, you will need to obtain an ITIN (Individual Taxpayer Identification Number).
This process can be a bit confusing, and the IRS does have strict requirements. Many applications are returned simply because of small procedural errors.
Here is a clear, step-by-step guide to help you apply for an ITIN correctly for the 2026 tax season.
What is an ITIN?
An ITIN is a tax processing number issued by the Internal Revenue Service. It is a nine-digit number that always begins with the number “9” (e.g., 9XX-XX-XXXX).
Key Takeaway: An ITIN is for federal tax reporting only. It does not authorize you to work in the US, it does not provide Social Security benefits, and it does not change your immigration status.
Who Needs to Apply?
You typically need to apply for an ITIN if you have a US tax filing requirement and you are not eligible for an SSN. For international founders and non-residents, this usually includes:
- Non-resident aliens who are required to file a US tax return (Form 1040-NR) to report business or trade income.
- Non-resident aliens claiming a reduced tax withholding rate under a tax treaty.
- Dependents or spouses of a US citizen or resident alien who are listed on a US tax return.
The “Golden Rule” of ITIN Applications
This is the most common misunderstanding about the process.
You generally cannot apply for an ITIN by itself.
The ITIN application (Form W-7) must usually be attached to a valid federal income tax return. You cannot simply request a number because you “might need it later” or because a bank asked for it.
- The General Process: You complete your tax return (Form 1040-NR), attach Form W-7 to the front of it, and mail both documents together to the IRS.
- The Exception: There are five specific exceptions where you can apply for an ITIN without a tax return (e.g., if you need it for third-party withholding on passive income). These exceptions require specific documentation from the financial institution or withholding agent.
How to Apply: The 3-Step Process
To successfully obtain your ITIN, follow these three steps.
1. Complete Form W-7
Download the latest revision of Form W-7 (Application for IRS Individual Taxpayer Identification Number).
- Check the box that describes your reason for applying (e.g., “Nonresident alien filing a U.S. federal tax return”).
- Ensure you enter your foreign address correctly.
2. Gather Your Identity Documentation
The IRS requires proof of two things: your identity and your foreign status.
The simplest document that satisfies both requirements is a valid passport.
If you do not have a passport, you must provide a combination of at least two other current documents (such as a foreign driver’s license and a national ID card).
Important Note: The IRS does not accept standard notarized copies of passports. You must submit either:
- Your original physical passport (which will be mailed back to you).
- A Certified Copy issued by the government agency that issued the passport (not a private notary).
3. Submit Your Application
You have three methods to file. Choose the one that works best for your situation.
- Option A: Mail Your Documents. You can mail your Form W-7, your tax return (1040-NR), and your original passport to the IRS ITIN Operation in Austin, Texas. Note that this means you will be without your passport for up to 14 weeks. Mail can sometimes be unreliable, so we recommend considering other options if you need your passport for travel.
- Option B: Apply in Person. You can visit designated IRS Taxpayer Assistance Centers (TACs) in the US. They can verify your passport in person and return it to you immediately. This requires an appointment and travel to the US.
- Option C: Use a Certifying Acceptance Agent (CAA). This is often the safest path for international founders. A CAA is a person or entity authorized by the IRS to verify your identity documents physically or via video interview. They submit the application on your behalf, so you do not need to mail your original passport.
Processing Times for 2026
The IRS takes time to process these applications.
- Standard Processing: About 7 weeks.
- Peak Processing (Jan–April): 9 to 11 weeks.
If your application is incomplete or if you send a copy of your passport that is not certified by the issuing agency, your application will be returned. You will receive a notice in the mail explaining what was missing, and you will need to resubmit.
Final Thoughts: Getting It Right
Obtaining an ITIN is a necessary step for tax compliance, but it doesn’t have to be stressful. The key is to be thorough with your documentation. The IRS needs to be 100% sure of your identity, so providing the correct, certified documents is the best way to ensure a smooth approval.
Secure Your ITIN with Clemta: We understand that mailing your original passport can be worrying. Clemta is here to help guide you through the ITIN application process, ensuring your Form W-7 is accurate and properly attached to your tax filings.
