You will not be allowed to enter the security checkpoint if your identity cannot be confirmed, you choose to not provide proper identification or you decline to cooperate with the identity verification process. TSA recommends that you arrive at least two hours in advance of your flight time.

Yes, it is actually possible to pass through a TSA checkpoint without a physical ID, though it is a much more intensive process. If you have lost your ID or forgotten it, the TSA has a verification process to confirm your identity using public databases. You will be taken aside to a specialized screening area where an officer will ask you a series of questions—similar to the security questions used by banks—regarding your past addresses, vehicles, or family members. If your identity is successfully confirmed, you will be allowed to proceed, but you will be subject to additional physical screening, which usually includes an enhanced pat-down and a thorough manual search of your carry-on luggage. It is important to note that this process can take an extra 30 to 60 minutes, and the TSA reserves the right to deny entry if they cannot verify your identity to their satisfaction. This exception does not apply to international travel, where a physical passport is a legal requirement.