Why Some Boarding Passes Say “SSSS”—And What Happens Next

Air travel can be stressful long before you reach the gate. From juggling baggage rules and navigating crowded terminals to dealing with delays and security lines, the process often feels overwhelming. Amid all this, some travelers notice a mysterious four-letter code printed on their boarding pass: SSSS.

That code stands for Secondary Security Screening Selection. It signals that the passenger has been flagged by the Transportation Security Administration (TSA) for additional screening before boarding. The designation often comes as a surprise, since travelers usually discover it only at the airport when security procedures suddenly take longer than expected.

Why Passengers Receive the SSSS Code

The SSSS designation is part of the TSA’s Secure Flight program, a risk-based system designed to strengthen aviation security. Passenger details—such as name, date of birth, and gender—are checked against government watchlists and compared with trusted traveler databases.