Ryanair, which saw annual passenger numbers climb by 8% to 129 million last year despite strikes across its network, has been ranked as the worst airline in the UK.

The no-frills carrier finished bottom of consumer group Which? Travel annual’s airline survey for the sixth consecutive year.

Ryanair was ranked the lowest for boarding, seat comfort, food and drink, and cabin environment – leaving it with an overall customer score of 40%.

At the other end of the scale, Jet2 impressed passengers with its service, seats and boarding and earned a customer score of 75%, according to the poll of almost 8,000 Which? members.

The top five were Guernsey-based Aurigny Air Service, Swiss, Jet2, Norwegian and KLM.

Ryanair’s reputation has declined so much that thousands of respondents told the consumer champion that they would never again fly with the airline again, even if it was cheaper than its rivals.

Of those who said there was one airline with which they would never travel, 70% named Ryanair.

The Irish carrier Ryanair cancelled flights and then refusing to pay its passengers compensation – resulting in the Civil Aviation Authority taking enforcement action.

Assigned seating on the airline can cost up to £30 each for a return journey, priority boarding, which includes a wheelie cabin bag, costs an extra £12 and the price of checking in extra luggage can also be significant, according to Which?

The airline also repeatedly tinkered with its luggage rules, risking confusion among passengers with three separate changes over the course of the year.

Which? Travel editor Rory Boland said: “Air fares might seem to be getting cheaper, but only if you don’t fancy sitting with your family and children or taking even a small cabin bag on-board.

“Increasingly you need a calculator to work out what the final bill will be, especially with Ryanair.

“It has spent the last two years cancelling thousands of flights, ruining hundreds of thousands of holidays and flouting the rules on compensation as well.

“The results of our survey show passengers are fed up. They should switch to one of their rivals, who prove that budget prices don’t have to mean budget service.”

Ryanair denied it had experienced significant problems as a result of the 2018 strikes, arguing that 90% of schedules remained operational on strike days. It also said that “it delivers industry-leading customer service” and claimed that its bag policy has been “simplified” by recent changes.

It claimed that decreased punctuality in 2018 was largely due to air traffic control strikes and added: “We’ve invested heavily in delivering on-time departures.”

It insisted that passengers will continue to book with Ryanair as “having the lowest prices wins every time”.

British Airways promised improvements in 2017 after scoring just 52% in Which?’s short-haul rankings and 50% for its long-haul services.

Bringing back a second meal on long haul and a pledge of more M&S sandwiches to buy on short-haul went some way to arresting the decline, yet passengers still gave food and drink just two stars and the overall customer score was still a “very underwhelming” 56% for short-haul and a slightly better 58% for long-haul flights.

EasyJet managed a better customer score than both Ryanair and BA, coming in the middle of the rankings with 63% – getting customers from A to B without too much drama for not much money.

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