When do I have to apply for a Social Security number for my newborn? Answer: There's no time limit on applying for a Social Security number for your newborn. However, you may want to do it right away, because you're required to include a child's Social Security number on your tax return to claim that child as a dependent. There are two ways to apply for a Social Security number for your newborn. The first is to apply at the hospital when the baby is born. A doctor or hospital representative will ask for information to complete your baby's birth certificate. Ask him or her to have your state's vital statistics office share this information with the Social Security Administration. You'll need to provide the Social Security number for each parent, although the application can proceed even if one parent's number is unknown or not available. Your baby's card will be mailed to you within a few weeks. If you do not apply for the Social Security card at the hospital, you can apply for the baby's number at a Social Security Administration office. You'll need to fill out an application (Form SS-5). Generally, you'll need to do the following: Provide both parents' Social Security numbers Show evidence of your child's age (the birth certificate), identity (a hospital record other than the birth certificate), and citizenship (the birth certificate) Show evidence of your identity (a driver's license or passport) To obtain a copy of Form SS-5, access the Social Security Administration website or call toll free at (800) 772-1213 to request one. Mail or hand deliver the completed application to your local Social Security Administration office.