Countless Brits will be jetting off during the summer holidays for a much-needed getaway. Whilst many eagerly anticipate their escape for months on end, one tiny detail could prevent them from stepping foot on the aircraft.
And it's all down to your boarding pass, which is mainly stored on our smartphones these days. Even with your passport and boarding pass at the ready by the departure gate, one particular code could derail your travel plans entirely.
Thankfully, Travel experts at SCS Chauffeurs – a premium airport transfer service – has warned holidaymakers to pay close attention to the SEQ number.
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Hadleigh Diamond, chief operating officer at SCS Chauffeurs, revealed toExpress: "SEQ stands for Sequence Number, and it tells airlines the order in which you checked in for your flight.
"A SEQ of 001 means you were the first to check in; 152 means you were the 152nd. While it doesn't affect your seat assignment or boarding group, it's crucial during overbooked flights, especially on budget airlines."

Airlines frequently oversell tickets, particularly during busy summer periods when kids are on their school holidays.
Hadleigh continued: "Airlines have to choose who gets involuntarily denied boarding. One of the factors used is the check in order. If you were one of the last to check in, you're more likely to be at the bottom of the priority list.
"When we arrange transfers, we often remind passengers to ensure they've checked in early, whenever possible, to avoid a potential flight issue."
The expert pointed out that airlines "tend to overbook flights" because not every traveller "turns up on the day".
The UK Civil Aviation Authority has reported that in excess of six million flyers were turned away at the gate worldwide last year, with a significant number oblivious to the fact that checking in early could have secured their spot.
In instances where a flight is so full that passengers get bumped or offloaded, carriers typically call for volunteers first.
However, if there are no takers, each airline follows its own protocol to decide who gets left behind.
A common method among many airlines is to use the SEQ number as a deciding factor. Those keen to know their SEQ should look for it printed close to or beneath the barcode – the lower the number, the better your chances.
It's worth noting that overbooking doesn't just impact those in economy; even flyers with pre-assigned seats aren't immune.
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