Social security numbers are required for both spouses if married filing jointly (only one is required for military spouses) and children. An Adoption Taxpayer Identification Number (ATIN) is also acceptable for children. If a child has an Individual Taxpayer Identification Number (ITIN), the family can still get the payment, but not the additional $500 for the child. If one spouse has an ITIN, the family is ineligible for the payment if filing a joint return.