For fliers who haven’t encountered it before, SSSS on a boarding pass stands for Secondary Security Screening Selection. It’s the Transportation Security Administration’s method of selecting passengers for additional security checks—and no amount of frequent flying, elite status, or pre-approval through a Trusted Traveler Program such as Clear, NEXUS, Global Entry, or TSA PreCheck guarantees immunity.
I learned this the tedious way in 2021, after my husband and I returned from a month-long trip to Türkiye and the Republic of Georgia. The international leg was smooth enough: We flew directly from Istanbul to Dallas and breezed through immigration without issue. The trouble began immediately afterward, when we tried to check in for our connecting flight home to Minneapolis.
First, the airline app wouldn’t issue our boarding passes. Then the self-service kiosk rejected us, too. It wasn’t until an airline agent printed our tickets that we saw it: the dreaded SSSS stamped across both of our boarding passes.
The TSA agent who scanned our boarding passes asked us to step aside while he radioed his supervisor. “We got a quad,” he said. That’s TSA shorthand for SSSS.
The screening was extensive: My husband and I were separated from our shoes, coats, and electronics; asked to pass through a metal detector and body scanner; and then subjected to a full-body pat-down. Our hands and feet were swabbed for trace explosives. Every inch of our carry-ons was unpacked and scrutinized; same for the checked luggage. The TSA agents were polite and professional, but the delay nearly caused us to miss our flight.
At first, I wrote it off as an annoying one-time hiccup. Then it happened again. We were SSSS’d flying from Dallas to Minneapolis, from Minneapolis to New Orleans, and from New Orleans back to Minneapolis. Each time, the first sign of trouble was the same: We couldn’t check in online or at a kiosk and had to see an agent for printed boarding passes. Each time, the extra screening added a fresh layer of stress to an already tight airport timeline.
While some groups of travelers are all too familiar with being flagged for invasive TSA screenings, others glide through security without incident—that’s when an SSSS code can come as a real surprise. And even when the process itself is quick, it can still throw off the delicate choreography of getting to the gate and settling in for a long flight.
What triggers SSSS on a boarding pass?
“Years ago, you could travel like a rock star to wherever you liked, on short notice, with no itinerary, pay in cash, stay overnight in party destinations, and do it all on a one-way ticket,” says Frank Harrison, Regional Security Director, Americas at World Travel Protection. “The world has changed.”
One common misconception, says Harrison, is that national aviation authorities like the TSA are the first screening line for passengers. It’s actually the airline. “When you book a plane ticket in today’s digitized world, your airline submits your name, gender, and date of birth to the TSA for clearance,” he says. “Airlines are motivated to ensure you are TSA-approved before you take to the skies [because] there are fines for allowing uncleared passengers onto aircraft.”
Travelers might be marked for booking one-way tickets, buying flights at the last minute, paying in cash, flying to or through countries deemed higher-risk, changing an itinerary frequently, or having a name that resembles someone on a Department of Homeland Security watch list. Sometimes, the selection appears to be random.