Maybe, but it depends on when the required Social Security Number (SSN) was issued.
Beginning with tax year 2018, you generally cannot claim the Child Tax Credit (CTC), Additional Child Tax Credit (ACTC), or American Opportunity Credit (AOTC) on either an original return or an amended return if the taxpayer, spouse, or qualifying child did not have the required SSN by the due date of the return, including any approved extensions.
Getting an SSN or ITIN later does not make you eligible to amend the return and claim these credits for that tax year.
Child Tax Credit and Additional Child Tax Credit
To claim the CTC or ACTC, your qualifying child must have an SSN that is valid for employment and was issued on or before the due date of your tax return, including extensions. If the child did not have the required SSN by that date, you cannot add the credit later by filing an amended return.
What If My Dependent Has an ITIN Instead?
If your dependent does not have a qualifying SSN but does have an Individual Taxpayer Identification Number (ITIN), you may still be eligible for the Credit for Other Dependents (ODC). This credit is worth up to $500 per qualifying dependent and can help reduce your tax bill.
Still have questions? Use this IRS Interactive Tool here to check if your dependent qualifies for the CTC or COD.