The consumer body compared the cost of a ticket to an Anne-Marie concert at Cardiff's Utilita Arena last November - which had a face value of £45 - between vendors.

Which? found that on average, the biggest ticketing sites add around 20% extra to the cost of a ticket but noted "charges can be lower or even sometimes higher than this".

Eventim charged a total of £56.37 after adding a £1.50 processing fee, £2.50 delivery and transaction fee, £5.62 booking fee and a £1.75 venue levy.

See Tickets charged a £7.37 booking fee, as well as another £2.50 in fees, for a total of £54.87.

Ticketmaster customers saw a final price of £55.60 after a £6.10 service charge, £1.75 facility charge and £2.75 order processing fee.

Rocio Concha, director of policy and advocacy at Which?, called the fees "sneaky drip pricing tactics", and said: "It's no surprise that music fans sometimes feel like they are being taken for a ride."

It comes after an Opinium poll released in January found that two thirds of adults in the UK believe music festivals are becoming too expensive.

They also found that 57% agree there should be a cap on how much music festivals can charge per person.

Musician Yungblud recently announced his own festival Bludfest, telling Sky News he was fed up with gigs and festivals being too expensive.

Sir Keir Starmer also said recently Labour would cap the resale prices of tickets and strengthen regulation on resale platforms if it wins the next general election.

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In a statement, Ticketmaster told Sky News: "Fees are typically set by and shared with our clients - venues, festivals, promoters, sports teams - who all invest their skill, resource and capital into getting an event off the ground. Ticketmaster supports legislation that requires all-in pricing across the industry."

A spokesperson for Eventim also told Sky News that booking fees are "set and agreed by the client," and any Venue Levy "is set and agreed by the Venue".

They noted that Eventim is responsible for the fulfilment fee and the processing fee, which they said "are charged per order not per ticket" and added: "Even e-tickets carry real costs due to the technology and staff deployed at events to ensure smooth access control."

They then said. "At eventim.co.uk, all mandatory fees are mentioned on page one of the booking process and nothing is added that the customer wasn't made aware of from the start.

"As a result of this transparency we get very few, if any, customers complaining that they were surprised by additional fees after entering the process."

Sky News has also contacted See Tickets for comment.