Which? tested five of the leading comparison websites by searching for 10 different flight routes which included London to Malaga one-way, Edinburgh to Athens return and London to LAX return.

Momondo was found to be the cheapest, offering the lowest fares for all 10 journeys, while popular comparison platform Skyscanner was matched or beaten by its fellow online aggregators for every flight.

It followed Cheapflights and Kayak, which tied for second place after finding the joint lowest price in eight of the searches.

Bottom of the pack was Google Flights.

Although all comparison sites are trawling the same airlines and travel companies to offer a range of options, the price discrepancy between flights was at times stark. Click here to read the full story.

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