The secret boarding pass code you never knew existed – and could see you kicked off a flight

YOUR boarding pass has a secret code which could get you kicked off your flight.

Many holidaymakers might already know about the dreaded SSSS code.

But there is another one that could cause problems at the airport.

On your boarding pass is the code SEQ with a number after it.

The code itself doesn't necessarily mean anything bad - this determines what order people check-in for their flights.

Headforpoints.com's Rhys Jones told : "One of the most interesting of the marks on a boarding pass is the "SEQ XXX" number.

"This denotes the order in which the passenger checks in for the flight."

However, the number could be the part that gets you kicked off the flight.

One person explained on Reddit: "It can play a minor role when somebody needs to be booted from an overbooked flight (or upgraded to a higher cabin)."

Someone else agreed: "It's used as mostly a tie-breaker in case of oversell situations."

So if you see a number like SEQ500, this means you were the 500th person to check-in.

If you are one of the last, then it may not be good news if the flight has been overbooked.

So next time you fly, you might want to try and check in as soon as it opens.

If you are quick enough you may even get the SEQ001 number - something loved by frequent flyers.

A code that is even worse is SSSS, which stands for "Secondary Security Screening Selection".

This means you have been selected for extra searches at the airport, which could delay you or even cause you to miss your flight.

A TSA source said that paying for tickets in cash or buying lots of one-way tickets could get you on the SSSS list.

Here's another bad boarding pass phrase which could cause problems.