The boarding pass is probably the most overlooked document of any trip. We print it, scan it, and stuff it in a pocket — or toss it — without a second glance.
But it contains far more than a gate number and a seat assignment. It carries alphanumeric codes tied to your booking, acronyms that signal your place in the boarding order, and letters indicating fare class.
Learning to read them is genuinely useful — not out of paranoia, but because it can make a real difference at the airport.
Of all the codes printed on a boarding pass, the one that raises the most questions is “RR.”
So what does it actually mean? What other boarding pass codes are worth knowing?
“RR” Is Not a Security Alert
When “RR” appears on a boarding pass, there are two possible explanations — and neither is cause for alarm.
The first depends on the airline.
For Southwest, “RR” stands for Rapid Rewards, the carrier’s loyalty program — confirmation that the ticket is linked to your account.
The membership number typically appears in the box directly above the letters, making the combination a loyalty marker rather than a red flag.
In other systems, “RR” has an operational meaning — it stands for “Random Review” and can trigger an additional security check near the boarding gate.
Extra screening may include identity verification, carry-on bag inspection, swabbing of bags and devices for explosive residue, or a brief interview with security personnel.
Passengers may be selected at random under airport security protocols, by automated risk-assessment systems, because of travel patterns or routes that trigger extra scrutiny, or under an airline’s or airport’s internal rules.
These selections are generally automated and are not based on personal history.
One important note: there is no global standard for boarding pass codes. Airlines and airports use distinct internal systems, so the meaning of “RR” can vary by carrier or ticketing platform.
When in doubt, staff at the check-in counter or boarding gate can confirm whether the code is a loyalty program marker or an indicator of additional screening.
The Codes Every Traveler Should Recognize
Some of the most common codes found on boarding passes include:
- PNR (Passenger Name Record), an alphanumeric code that uniquely identifies a traveler’s itinerary;
- FQTV (Frequent Traveler), which indicates enrollment in a loyalty program; and
- SEQ or SEQ NO, the sequence number that marks the boarding order.
The most dreaded code, by far, is SSSS. The letters stand for “Secondary Security Screening Selection” and designate certain passengers for a more thorough inspection by the TSA.
The code was introduced by U.S. authorities as an additional security measure following the Sept. 11 attacks.
Passengers flagged with SSSS generally cannot check in online or at self-service kiosks. They must approach the counter, where an agent prints the boarding pass bearing those four letters.
The screening that follows includes a metal detector and full-body scanner, a complete pat-down, and swabbing of hands and feet for traces of explosives.
The designation can be random, but it can also be triggered by certain patterns: booking a last-minute ticket, paying in cash, flying to countries the U.S. State Department considers high-risk, or having a name that resembles one on a watchlist.
What’s Hidden in the Barcode
Beyond what is printed on the surface, the boarding pass barcode holds far more data than most people realize.
According to cybersecurity researcher Brian Krebs, a boarding pass barcode can give criminals easy access to a traveler’s phone number, future travel plans, and frequent flyer number.
By uploading a photo or screenshot of the barcode or QR code to a free online reader, anyone can access the frequent flyer number, the personal data tied to that account, and the details of upcoming flights.
With that information, someone could also change seat selections, cancel flights, or modify the account PIN.
Security expert Etay Maor has noted that airlines pack so much information into the barcode for a functional reason: when a problem arises, an airline representative can scan the pass and instantly pull up the passenger’s email address, travel itinerary, and other details needed to help them on the spot.
The problem is that most travelers have no idea how much sensitive data they’re walking around with.
Why You Should Think Twice Before Posting Your Boarding Pass
The warning has circulated in cybersecurity forums for years, and most people still ignore it. Posting a photo of your boarding pass on social media is a genuine risk.
In 2015, cybersecurity researcher Brian Krebs documented on his blog KrebsOnSecurity how one of his readers took a photo of a boarding pass that had been posted on Facebook, uploaded it to a free online barcode reader, and gained access to the passenger’s name, frequent flyer number, and booking reference number.
With those details, he accessed the airline’s website, where he could see all future flights tied to the account, the passenger’s contact information, and could have canceled the trip or reassigned the seats.
Deleting the boarding pass from your phone once a trip is over reduces the risk of an old pass — still loaded with personal data — falling into the wrong hands. For paper passes, the advice is equally straightforward: shred or tear them up before throwing them away.
In the end, a boarding pass is far more than a ticket onto a plane.
There’s more to it than meets the eye — and understanding it is the first step toward handling it with care.
