Can you claim foster kids on taxes?

It's not 6m & 1 day, it's 183 days (365/2 + 1). If they are less than 6m old and they came to your home from the hospital then you can also claim them. However, if they went home with anyone else and then came to you then you can't claim them.Yes, they do have to have SSNs. So you will need to get them from the CW. If the kids came into care at birth DHS would have filed for a SSN. Also, at this point the BPs may have claimed them, which would make yours rejected if you efile. Then you would have to paper file with proof that you've had them for the alloted amount of time.