I just got my new born son’s SSN. Can I file an amendment tax return? And how can I do that?

[rjs]

In what year was your son born? If he was born in 2024, you could not have filed your 2024 tax return yet, so there is nothing to amend. You will just include him when you prepare your 2024 return. If he was born in 2023, why did it take so long to get a Social Security number? There must be something unusual about the situation.

[Opus 17]

If you are asking about 2023:

To receive the child tax credit (up to $2000 or EITC, the dependent must have a valid SSN issued before the due date of the tax return (including extensions).  That would have been April 15, 2024 or October 15, 2024.  Since you did not receive the SSN before those dates, you can't get the child tax credit or EITC by amending a 2023 tax return. 

If you paid for child care so you (and your spouse if married) could work, then I believe you could claim the child and dependent care credit with a late SSN.