The Surprising Reason Some Boarding Passes Show “SSSS”

Air travel is already challenging for many passengers. With tasks like checking bags, moving through crowded terminals, and watching gate information, the experience can become stressful even on routine travel days.

That stress can increase when unexpected issues arise. One detail that often surprises flyers is a small code printed on their boarding pass—something many don’t notice until they are already at the airport.

If your ticket shows the letters “SSSS,” it refers to Secondary Security Screening Selection. This code means the Transportation Security Administration has flagged you for extra security procedures.

The designation comes from the Secure Flight program, which evaluates passengers before they reach TSA checkpoints. The system compares traveler details—such as name, birthdate, and gender—to both trusted traveler databases and federal watchlists to determine risk levels.

Receiving the SSSS label doesn’t mean you’ve done anything wrong. Most of the time, passengers are chosen randomly or due to factors like booking very close to the departure time, flying internationally, or having incomplete travel information.

Extra screening may include more in-depth bag checks, swabbing for traces of explosives, or additional verification of your identification. These steps are designed to ensure safe travel for everyone.

Passengers can ease the process by arriving with plenty of time, keeping their items organized, and following standard TSA rules, like removing electronics and keeping liquids within limits. Understanding the meaning of “SSSS” helps you prepare so the rest of your trip can proceed smoothly.