What this notice is about We have important information about your child's Adoption Taxpayer Identification Number (ATIN). Your child's ATIN expires in 3 months. What you need to do Complete Form 15100, Adoption Taxpayer Identification Number (ATIN) PDF Extension Request, included with your notice if you received a Social Security number (SSN) for your child, or; Apply for a one-year extension of this ATIN by completing Form 15100, if you don't have an SSN. Detach notice stub, mail it with Form 15100 in the envelope provided. If you prefer, fax your information to the fax number in the notice using either a fax machine or an online fax service. Protect yourself when sending digital data by understanding the fax service’s privacy and security policies. You may want to Call us at the number listed in your notice. See additional information on Adoption Taxpayer Identification Number. Frequently asked questions What can I do if I don't have a Social Security number (SSN) for my adoptive child? You can request an extension before your assigned ATIN expires by completing Form 15100 included with your notice. The extension is only valid for 1 additional year. Reference tools Publication 1, Your Rights as a Taxpayer Full list of tax forms and instructions 도움이 필요하십니까? 귀하를 대신해 IRS와 연락하도록 타인에게 권한을 부여할 수 있습니다(영어). 저소득 납세자 클리닉(영어)으로부터 도움을 받을 수 있는지 알아보십시오. 온라인에서 필요한 정보를 찾을 수 없는 경우 통지서 및 서신 상단에 기재된 IRS 번호로 전화하십시오. 서신이나 통지서를 받지 않았다면 전화 상담을 이용하십시오. 스스로 과징금 문제를 해결할 수 없는 경우 IRS내 독립기관인 납세자 보호 서비스에 문의하십시오.