You check in and print it out 24 hours before boarding your flight, or maybe you download it to your phone. Either way, your boarding pass is a key item that allows you entry onto your flight. It serves as an identity document, a security pass, an information booth, and a key to your passageway. But what do all those seemingly random characters and symbols on your pass actually mean? Here, we dive in, with a little help from travel company Boxever and the Huffington Post.
One of the most recognizable things on your boarding pass is the bar code. The magnetic strip, called BCBP, or bar-coded boarding pass, often appears on the bottom right side of your boarding pass, but there’s no hard and fast rule about its placement. The bar code itself is 2D, and must meet the standards of the International Air Transport Association (IATA), an airline trade group that sets criteria for consistency across the airlines and countries. The bar code is often scanned at the gate and helps speed up the boarding process. The scanner also records the information, so gate agents and the crew on the plane can easily tell how many people have boarded, what seats are taken, and how many bags have been checked.
Your unique identifier
There’s a six-digit alphanumeric code that appears on your boarding pass. That’s your PNR, or Passenger Name Reference, otherwise known as your record locator or reservation code. This randomly generated sequence is what you need to type in to retrieve your boarding pass, and is what identifies you as a unique passenger—you know, in case there’s someone else with your exact first and last name on your flight. Among other things, this PNR holds information about your meal preferences or special requests. It’s one of the main reasons you shouldn’t throw away your boarding pass in a public trash can, as someone may be able to pull your information using your reservation number or bar code.
Flight code and number
Look for two uppercase letters, followed by a four-digit number. The letters are the airline code, or the numbers universally recognized to represent the name of the airline in shorthand. Some are obvious—AA is American Airlines, for example—but others are not, like JetBlue, which is B6. The flight number is determined by the airline, using a complex algorithm that takes into account past and current airline flight numbers, as well as things like other airlines with similar sounding numbers scheduled to fly through the same airspace at the same time. This helps avoid potential confusion with pilots and air traffic control.
A floating letter
You may notice a letter on your boarding pass that’s distinct from all the others—a lonely “B” hanging out by itself, for instance. That letter may be the most classist part of your ticket (aside from your seat assignment). The stray letter may appear next to your seat assignment, flight number, or even just adjacent to the date and time of your flight. Different letters mean different things to different airlines, but generally, the letter marks your airline status, aka, your likelihood of getting an upgrade based on your loyalty status and what seat you booked. An “A” or “F” mean first-class treatment, while a “B” often means you’re more likely to get upgraded than if you have a “Q” or a “Y” on your ticket—the latter two are typically the cheapest economy fares.
Note the line on your boarding pass that says “operated by,” which tells you what you may have missed during the booking process: that your flight is actually not being flown by the airline you thought you were traveling with. Often, airlines sell tickets on their sites for flights operated by partner airlines, sometimes known as codeshare flights, or subsidiary ones on regional jets that they own but don’t operate. American Eagle is one example, as it’s owned by American Airlines but operated by a different company with distinct rules and structuring.
There’s no way to know with certainty whether you’re getting frisked by security at the airport, but if there’s an “SSSS” on the bottom of your boarding pass, odds are you will. This code marks you as a higher security risk, or “Secondary Security Screening Selection,” which means you’ve been pre-selected for additional security screening. (“Secure Flight is a risk-based passenger pre-screening 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 watchlists,” the TSA told Business Insider.) While the criteria for how one gets on the list isn’t clear, it includes people who appear on the No Fly List and the Do Not Board List put out by the U.S. government’s Terrorist Screening Center and the Centers for Disease Control, respectively.
You’ll see an S/O on your boarding pass if you have a stopover or layover, and “SPTC” if you have a stopover that lasts longer than a few hours, in which case the airline may even put you up in a hotel.
This post originally appeared on CNTraveler.com.