An ATIN is a temporary, nine-digit number issued by the IRS for a child being adopted domestically when the adoptive parents cannot obtain a Social Security Number (SSN) in time to file their tax return.
- Purpose: Allows adoptive parents to claim the child as a dependent and access tax benefits. An ATIN is intended for temporary use and should be replaced with the child’s Social Security number when available.
- Issued by: IRS (via Form W-7A).
- Temporary: Replaced by an SSN once the adoption is finalized.
- Use: Only for tax purposes—not valid for work or other identification.
Comparison: ATIN vs. ITIN vs. SSN
| Feature | ATIN | ITIN | SSN |
|---|---|---|---|
| Full Name | Adoption Taxpayer Identification Number | Individual Taxpayer Identification Number | Social Security Number |
| Issued By | IRS | IRS | Social Security Administration |
| Purpose | Temporary ID for adopted children without SSNs | Tax ID for individuals not eligible for SSNs | ID for U.S. citizens and eligible residents |
| Who Uses It | Adoptive parents filing taxes | Nonresident aliens, foreign nationals, dependents without SSNs | U.S. citizens, permanent residents, and eligible workers |
| Valid For Work? | ❌ No | ❌ No | ✅ Yes |
| Valid For Tax Filing? | ✅ Yes | ✅ Yes | ✅ Yes |
| Temporary or Permanent? | Temporary | Permanent (until status changes) | Permanent |