A Taxpayer Identification Number (TIN) is a unique number used by the Internal Revenue Service (IRS) to identify individuals and entities for federal tax purposes.
Types of TINs
- Social Security Number (SSN)
Issued by the Social Security Administration to U.S. citizens and individuals authorized to work in the U.S. - Employer Identification Number (EIN)
Used by businesses, estates, trusts, and some organizations. - Individual Taxpayer Identification Number (ITIN)
Issued by the IRS to individuals not eligible for an SSN who need to file a federal tax return or be listed on one. - Adoption Taxpayer Identification Number (ATIN)
A temporary number issued by the IRS for a child in the process of adoption when an SSN has not yet been assigned.
SSN vs. ITIN vs. ATIN: What’s the Difference?
| Feature | SSN | ITIN | ATIN |
|---|---|---|---|
| Authorized to Work | Yes | No | No |
| Social Security Benefits | Yes | No | No |
| Used for Tax Filing | Yes | Yes | Yes |
| Earned Income Tax Credit (EITC) | Yes | No | No |
| Child Tax Credit (CTC) | Yes | No | No |
| Credit for Other Dependents | Yes | Yes | Yes |
| Immigration Impact | May apply | None | None |
| Temporary Use | No | No | Yes |
What ITIN and ATIN Holders Cannot Claim
Earned Income Tax Credit (EITC)
- The taxpayer, spouse (if MFJ), and qualifying child must all have valid SSNs
- ITINs and ATINs are never valid for EITC
Child Tax Credit (CTC)
- The child must have a valid SSN issued by the SSA
- Children with ITINs or ATINs do not qualify
- An ATIN is not acceptable for the CTC
Social Security Benefits
ITIN and ATIN holders are not eligible for retirement, disability, or survivor benefits
SSN‑Required Deductions (2025 and later)
Certain deductions and credits require the taxpayer (or at least one spouse on a joint return) to have a valid SSN.
Taxpayers using only ITINs are not eligible for these benefits.
What ITIN and ATIN Holders Can Claim
- Credit for Other Dependents (ODC)
- Child and Dependent Care Credit
- American Opportunity Tax Credit (AOTC) (student must have a valid TIN)
- Lifetime Learning Credit (LLC)
- Premium Tax Credit (PTC)
Important clarification:
ATINs do NOT qualify a child for the Child Tax Credit or EITC.
ATINs are accepted primarily for filing status, dependency claims, and adoption‑related processing.
Do ITINs and ATINs Expire?
ITIN Expiration
- Expires if not used on a federal tax return for 3 consecutive years
- May also expire based on middle‑digit rules announced by the IRS
ATIN Expiration
- Temporary by design
- Expires:
- 2 years after issuance, or
- When the child receives an SSN (whichever happens first)
How to Renew or Replace
- Renew an ITIN:
File Form W‑7 with required documentation - Replace an ATIN:
Once the child receives an SSN, update the return going forward using the SSN
Why This Matters
Understanding the differences between SSN, ITIN, and ATIN helps agents:
- Prevent incorrect credit claims
- Avoid IRS rejections or audits
- Guide taxpayers on why a credit was denied
- Support ITIN renewals and ATIN‑to‑SSN transitions
Red Flag: If a taxpayer expects EITC or CTC and the child does not have an SSN, the credit is not allowed — no exceptions.