22/09/2017 10:47 BST | Updated 20/10/2017 17:15 BST

This Is What It Means If You Have 'SSSS' Written On Your Boarding Pass

You could be in for a delay.

If you’re travelling to the US, check your boarding pass for a stamp saying ‘SSSS’.

The four letters stand for “Secondary Security Screening Selection” and if they’re printed on your boarding card, it may mean you’re delayed getting through security.

The letters mean you’ve been selected for enhanced screening before getting into the country, meaning staff are likely take extra interest in your luggage and you may be more likely to be searched.

The SSSS system is nothing new and was introduced following the 911 terrorist attacks, but it’s been hitting headlines again this week following a number of people tweeting photos of their boarding cards over the summer. 

A Transportation Security Administration (TSA) spokesperson previously told NBC News passengers are selected on the SSSS system at random by computer, but others have suggested you may be added to the list if you’ve recently travelled to certain destinations, such as Turkey.

Recently speaking to Business Insider, a TSA spokesperson clarified: “SSSS stands for Secondary Security Screening Selection and it appears on a passenger’s boarding pass when they’ve been selected by TSA’s Secure Flight system for enhanced security screening.

“Secure Flight is a risk-based passenger prescreening program that enhances security by identifying low and high-risk passengers before they arrive at the airport by matching their names against trusted traveler lists and watch lists.”

Either way, it’s a good idea to leave yourself extra time at the airport if you’re travelling to America in case you end up seeing those four letters. 

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