The introduction of “basic economy” fares by airlines on long-haul routes is making airfares more attractive to customers, but they often come with reduced service and a host of potential extra charges.

Those were the findings of add-ons specialist Airport Parking and Hotels (APH), which carried out a study examining the lowest fares of 21 major airlines including British Airways, Virgin Atlantic, Thomas Cook and easyJet, to show what is included and excluded from their prices.

The so-called “unbundled” fares, which were first pioneered by the low-cost carriers, are designed to offer the lowest headline price. But increasingly customers have to pay extra for previously included services such as hold baggage, seat selection, airport check-in and onboard food and drink.

The picture across airlines is far from uniform, with each having different fees for the various ancillaries associated with air travel, and this is particularly true in the case of luggage.

The majority of airlines – 19 out of the 21 researched – allow cabin luggage onboard, with 10 carriers also permitting passengers to store one small personal item under the seat in front.

For long-haul flights, nine airlines including Emirates and Qantas still allow passengers to check in luggage as part of their cheapest fares.

But two carriers, Wizz Air and American Airlines, do not currently allow passengers to store bags in their overhead lockers as part of their most basic fares.

“When the baggage allowance does not suffice, all the airlines allow passengers to purchase additional luggage space for a fee, varying from £8 with Wizz Air to £171 with Qantas, depending on the flight route and bag weight,” says Nick Caunter, managing director of APH.

“However, travellers should note that it may be best to purchase additional luggage allowance online prior to departure, since many airlines charge more for add-ons bought offline.”