An ITIN, Individual Taxpayer Identification Number, is a 9-digit tax processing number issued by the IRS to individuals who are required to have a U.S. taxpayer identification number but are not eligible for a Social Security Number, SSN.

You may need an ITIN if you are not eligible for an SSN but need to file a US tax return, claim treaty benefits, report US income, or meet federal tax compliance requirements.

The main document is usually a valid passport. In some cases, additional identity or foreign status documents may be required depending on your application reason.

Processing time depends on IRS workload, document accuracy, and whether additional information is requested. It can take several weeks after submission.

No. Non-US residents can apply for an ITIN from outside the United States if they have a valid US tax purpose.

In some cases, an ITIN may support a US bank account application, but approval depends on the bank’s own requirements and verification process.

An ITIN does not directly register a business, but it can support tax filing and compliance for individuals connected to a US business.

No. An SSN is issued to eligible individuals for tax and employment purposes. An ITIN is only for federal tax identification and does not provide work authorization or immigration status.

An ITIN can expire if it is not used on a federal tax return for a certain period. If expired, it must be renewed before filing.

Yes, if your ITIN has expired or is about to expire and you need it for US tax filing, you should renew it before submitting your tax return.

Yes. ITINs are issued for federal tax filing and reporting purposes for individuals who are not eligible for an SSN.

If your application is rejected, the IRS usually provides a reason. Startitup can help review the issue, correct the application, and guide you on the next steps.