Boarding passes were first written out and handed to passengers at airport check-in for decades, ever since people started to fly commercially. In 2008, the International Air Transport Association (IATA) proclaimed that commercial airlines can no longer issue handwritten boarding passes. Today, most of the world continues to issue paper tickets issued electronically, but the use of mobile passes is increasing.

Nonetheless, regardless if you’re holding a mobile or printed ticket, there are character combinations that signify different things. And no, we’re not talking about the Gate, Seat, Departure/ Arrival Time or Airline Number. So, do you know what all those other letters on your boarding pass mean?

Reservation Code

Your boarding pass contains six characters, also known as a reservation code that the system generates when you book your flight via call, online or at the airport. But did you know that these letters and numbers on your boarding pass contain a lot of information about you (the passenger) including first and last name, flight information, meal preferences, and special service requests (i.e. uses a wheelchair)? If anyone gets a hold of your reservation code (for instance, you throw it away in a bin in a public area), that person can find out information about you.

Single Letter

Your boarding pass will have a single letter somewhere, either next to the flight number, date and time of departure/arrival, or even next to your seat number. This letter has no association with the gate or seat, rather it has to do with your flying status. Airlines identify of what each letter stands for differently, but for the most part, having a letter “A” or “F” could signify someone sitting in first or business class, whereas a letter “B” references a possibility to upgrade into a better class, and if you see a “Q” or a “Y”, then that identifies you as being an economy passenger.

SSSS

One of the most dreaded four letters you’ll see on your boarding pass is “SSSS”. And we say dreaded because it means that you have been randomly selected to go through extra security screening. “SSSS” stands for Secondary Security Screening Selection, which will require you to have all your carry-on bags and anything you are carrying to be thoroughly examined and swiped to make sure you’re not bringing anything dangerous onto the plane or to the destination you’re traveling to. Sometimes, these selections are random, but if you are one of the few selected, you are either one of the random passengers that are identified as “low-risk” or one that’s “high-risk” (i.e. those on a No Fly List or a Do Not Board List).

Stopovers and Layovers

If you ever notice the letters S/O on your ticket, that means you have a layover or a stopover. If you see the letters “SPTC”, then that signifies your stopover is longer than just a few hours.

Do you ever pay attention to all those letters on your boarding pass? And, do you know what they all mean?