Domestic Travel Documents Needed for Adults & Children
While it doesn't require quite the same amount of preparation to travel with kids inside the U.S. as it does to take those same kids out of the country, you do have to make sure you are prepared for your next domestic travel adventure. Adults have some very clear requirements for what identification they'll need, but depending on the age of the child, the requirements can vary from airline to airline.
Adults are required to show identification when checking in at the TSA checkpoints. Acceptable forms of ID include any state, federal or tribal identification card, including a passport, military ID card, permanent resident card, border-crossing card, state ID card or driver's license. If you're traveling and lose all your ID cards, you may be able pass through the checkpoint by going through a special screening with TSA officers, but that's not common.
Kids under 14
According to the Transportation Security Administration, kids are not required to show any identification at TSA checkpoints; still, some airlines require a birth certificate for children under 14 to prove their age. To avoid any hassles, travel with at least a copy of your child's birth certificate, or for the best-case scenario, obtain a passport for your child.
Kids 15 to 17
While kids 15 to 17 are still considered minors in the eyes of the TSA, some airlines require that they have some kind of identification when they're traveling alone. The rules can be somewhat looser than for adults; a school-issued ID card or a library card may be all that is required. For teens traveling alone, be sure to check with your individual airline.
If you're traveling with children and their parents are not with you, prepare to be asked to provide documentation that you have permission to travel with the child. Ask the child's parent to sign a "Travel Consent Form," available free on many legal websites, and have it signed in the company of witnesses. Take the form along with you and have it handy when you fly. While this may not be an issue on a domestic flight, it never hurts to be prepared.