My understanding is that if the parents are not married, only one can claim the child as a dependent and EIC. Is this true if the other parent does not file a return due to not enough income? Also, can you amend 2024 taxes to claim EIC after the fact?
If you are a non-married couple who live together with your child, then only one of you can claim the child(ren) and the one not claiming the child does not enter anything at all on their tax return about the child. The “sharing” of child-related credits you may have heard about is only possible between divorced or never married parents who live apart and share custody and who have a written agreement to share the credits. The child’s SSN can only be entered on one tax return. Any other return with the child’s SSN on it will be rejected. If you are a family, then work out how to share the refund between yourselves.
If you need to amend a past year return:
Use a mailing service like certified mail to track so you will know it was received since you will have a long wait.
Do not expect quick results from amending. It can take four months or more for the IRS to process an amended return.
You can watch for information here:
https://www.irs.gov/filing/wheres-my-amended-return