ITIN
ITIN is a US tax processing number issued by the IRS to individuals who must pay US taxes but are not eligible for a Social Security Number. ITINs are nine digits beginning with the number 9 and are formatted similarly to SSNs (NNN-NN-NNNN).
The ITIN program serves several populations: non-resident aliens with US tax obligations (foreign investors with US-source income), spouses and dependents of US citizens or residents who don't qualify for SSNs, undocumented residents who need to file US tax returns, and others whose tax-filing requirements don't fit the SSN-eligibility framework.
ITINs are tax-only — they do not authorize work in the US, and they are not Social Security Numbers. ITINs do not, by themselves, change the holder's immigration status. However, ITINs are used by some employers and financial institutions as a US-tax-identifier for ITIN-holders who need to operate in the US economy.
For financial services, ITIN-holders represent a meaningful customer segment. Many banks now offer 'ITIN-mortgage' products specifically for ITIN-holders (typically with alternative documentation requirements and slightly different LTV limits). Some credit-card products and personal-loan products are similarly available. Wealth platforms serving ITIN-holders need their onboarding workflows to handle ITINs as first-class identifiers, not as edge-case exceptions.