An Adoption Taxpayer Identification Number (ATIN) is A short lived nine-digit number issued through the IRS to individuals who are in the entire process of lawfully adopting a U.S. citizen or resident child but who can not get an SSN for that kid in time to file their tax return. https://pmaccounting59370.thenerdsblog.com/39260311/the-ultimate-guide-to-tax-slayer