A start-up firm managing and marketing short-term lets has had three complaints upheld against it by the Advertising Standards Agency.

Airsorted was found to have breached ASA rules with a website and social media campaign that it ran in January and February this year.

The campaign featured a grid comparing services offered by Airsorted and rival Hostmaker.

The grid showed services such as “Personal dedicated service . . . You get a client success manager who knows your home”, with ticks against each category to claim that Airsorted offered these, but that Hostmaker did not.

A second campaign in February claimed that Airsorted was the world’s biggest Airbnb management company, adding: “We can help you earn around 300% more from your property”. It also mentioned a one-bed property in Whitechapel, London, which it said “made £3,112 last month”.

The watchdog ruled Airsorted was unable to substantiate the comparative claims it made between itself and Hostmaker, which made the complaint.

The ASA also noted that while Airsorted said it would make changes to the first advert, it did not say what those changes would be. The ASA said that Airsroted had not provided any substantive response to the complaint.

In its ruling the ASA said: “We told Airsorted to ensure that future ads did not make claims by comparison with identifiable competitors, unless they held adequate evidence to substantiate and verify the claims.”

Airsorted went live in London in 2015, and values itself at over £26m. It is backed by investors including Atami Capital, Concentric, Maxfield Capital and Pi Labs while a recent crowdfunding campaign raised £6m.

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