A TRAVEL expert has revealed the pricey mistake passengers often make that sees them paying too much for their luggage. Kyle Potter, executive editor of the website Thrifty Traveler , has given holidaymakers his advice on the best time to add luggage to your basket to make sure it is as affordable as possible. Potter also recommends sticking to just carry-on bags if possible as often bags are weighed and priced accordingly.

Many airlines even allow for a free carry-on for all your personal belongings on the flight. But for those airlines who don't supply free baggage Potter's tip could be vital. He says passengers should use the bag cost calculator provided by many airlines to figure out how much any extra luggage will cost - but to always do it before you buy a plane ticket.

Knowing the weight of your luggage means you can adjust your ticket type to suit your baggage needs. Paying for almost everything costs a lot more at the airport compared to the weeks leading up to your trip so deciding on your luggage allowance pre-flight makes it as cheap as possible. Potter told the Washington Post : “Adding it to your ticket as you check out is always going to be the cheapest time to do it.

"On some airlines, paying at the airport to check or carry on a bag can cost more than $75. “It gets pretty disgusting in some cases to pay for that bag at the airport. "You’ve got to do the mental math at the time you’re booking your flight.

” It comes as a travel guru issued a warning t.