Cabin bag and seat selection fees can quadruple the cost of flights, research has revealed.

A study by UK consumer researchers Which? found that added fees make it hard for passengers to compare the true cost of flying with different airlines.

Which? is calling for the UK government to ensure that airline fees are included in laws cracking down on ‘drip pricing’ – charges that are added or ‘dripped’ onto the advertised price.

The Digital Markets, Competing and Consumers Act 2024 is due to come into effect in April 2025, which should end the drip pricing tactics. However, Which? says it is unclear whether add-on charges beyond unavoidable booking or transaction fees will be included.

The researchers found that selecting add-ons with Wizz Air on some routes can increase the initial advertised charge by over four times, while prices on other routes with Ryanair and easyJet can more than double the advertised rate.

Which? carried out a snapshot analysis of 15 “ultra-low-cost” flights with budget carriers such as easyJet, Ryanair and Wizz Air, and found that Wizz Air charged the most for extras on average.

They discovered that when booking a return flight from London Luton to Lyon in France, Wizz Air advertised the flight for just £29 per person, yet when choosing the airline’s ‘Wizz Smart’ fare, which includes a 10kg bag, a standard seat and priority boarding, the price rocketed to £124 per person.

By adding on these extras, the price quadrupled, with 77 per cent of the final price being made up by additional fees.

When analysing Ryanair flights, Which? found that around half of the final fare was, on average, made up of additional fees. A journey from London Stanstead to Nantes was listed at £33, but when selecting a ‘Regular’ fare, which adds seat selection, a cabin bag and priority boarding, the price more than doubled to £84.

EasyJet was also found to have done similar. A flight from Luton to Malaga was shown as costing only £41, but when adding on seat selection, a cabin bag and priority boarding, the cost soared to £111, with 63 per cent of the final fare being ‘dripped’ fees.

The consumer champion has said that tactics like these can increase a family holiday by hundreds of pounds. They are also calling for a ban on charging parents to sit next to their children on flights.

While some airlines say they will do their best to seat families together, they do not always guarantee that parents can sit with children, which may prompt travellers to pay to ensure their family can be together.

Rocio Concha, Which? director of policy and advocacy, said: “Sneaky dripped fees can hugely change the final price people pay for goods and services and this is particularly true with flights, where the difference between the advertised price and the final fare can easily reach hundreds of pounds for a family.

“Which? is calling on the government to ensure that additional fees for add-ons like seat selection and luggage are made clear at the very start of the booking process, to ensure travellers can easily compare the final price they’ll pay with different airlines.

“Unfair charges for parents to sit with children on flights should also be banned.”

A Wizz Air spokesperson said: “As an ultra-low-cost carrier, we allow passengers to choose which services they wish to purchase so we can offer the most affordable travel opportunities in the entire industry. Optional add-ons are not required to fly, and we believe that customers should be offered the choice and flexibility to choose the right products.

“The cost of our fares and optional add-ons are dynamic and are based on multiple factors including seasonality, demand and supply of certain routes and destinations, which this research fails to consider. It also fails to compare like-for-like routes between the airlines to help travellers make an informed decision.

“Our fares start from £12.99, seat selection can also be added from as little as £4, and 10kg of checked baggage starts from £8. Many of our regular customers choose to fly without optional add-ons, saving money every time they travel.

“To get the very best prices, passengers should always book directly with Wizz Air as Online Travel Agents will charge additional fees.”

An easyJet spokesperson said: “easyJet customers only pay for the ancillary products they want so we aim to provide customers with choice and this enables us to keep fares low.  Around a third of easyJet’s customers choose to only pay for the fare and free under seat bag without adding any extras at all and our algorithm will always aim to sit families together.

“Nearly 90 million passengers will choose to fly with easyJet this year and 50 per cent of our passengers pay fares on average less than £50 so there is no doubt customers receive very good value for money.”

A Ryanair spokesperson said: “This is more fake news from Which. The price of Ryanair’s seat selection starts from €4, not the £8 price wrongly quoted by Which. We don’t charge “parents” to sit with children. Rather the child seats are provided free of charge when they sit beside one parent, who must reserve a seat for a fee of €4.”

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