Adverts by four of Britain’s biggest hotel and travel firms have been banned for stating misleading minimum prices for rooms.

The Advertising Standards Authority (ASA) upheld complaints against the Hilton hotel group, Travelodge, Booking.com and Accor over their use of eye-catching so-called “from” prices.

The watchdog found only a small number of rooms actually available to book at the promoted price and concluded the adverts overstated the deals.

It said this was unfair on those looking for good deals or seeking to make informed choices about where to book.

ASA operations manager Emily Henwood said: “Advertised prices must match what’s really available. If only a few rooms are actually offered at the price shown, or it only applies to a specific date, then this information must be made clear to avoid misleading people.

“People should be able to trust the prices they see in ads and these rulings show that we will take action if the rules are broken.”

The ASA used AI to identify the misleading adverts as part of a wider probe into the availability of advertised hotel prices.

The Hilton hotel group was rebuked over two adverts, one reading “Hampton by Hilton Hamilton Park From £68”, and the other advertising stays in Newcastle from £59.

The ASA asked Hilton whether it could back up the claims, with the hotel offering evidence that rooms were bookable at the hotels on the respective dates the adverts were viewed.

But the ASA concluded Hilton had exaggerated the availability of the advertised rooms, leaving potential customers at risk of being misled. It ordered the chain not to publish the adverts again and warned Hilton to ensure any future price claims reflect deals available for “a significant proportion of rooms”.

A Hilton spokesperson said the company had experienced a “glitch” with its ad provider in April, causing two adverts to display “incorrectly”.

“Although rooms remained bookable for guests at the advertised rates, we are working to ensure that we can better evidence this in future in a way that is aligned to ASA reporting requirements,” they said.

Hilton said it took seriously its responsibility to ensure transparency around advertising and pricing.

Travelodge had two adverts banned – one offering rooms in Nottingham Riverside “from £25” and the other rooms in Swansea “from £21”.

The ASA found that the advertised prices were only available for a single night’s stay, warning Travelodge in future to ensure deals are available “across a range of dates”.

A Travelodge spokesperson said it recognised the need for clarity and transparency in pricing and is working with Google to ensure its adverts are clear and comply with the ASA’s guidelines. It said the relevant advert was removed before the ASA’s ruling.

Similar findings were issued against Booking.com and hotel group Accor, while staycation chain Butlins was criticised for changing the deadline of a sale it promoted via email.

Accor told the ASA it believed its adverts were accurate as rooms were available at or below the headline prices in the days following their publication.

In a statement to the BBC, Accor said the specific advertisement criticised by the ASA had not been shown since.

“We are taking this opportunity to further strengthen our existing internal processes,” a spokesperson for Accord said.

Booking.com sent the watchdog a screenshot demonstrating that seven bookings had been made at the prices it advertised.

A spokesperson told the BBC that Booking.com accurately displays price and availability at the time advertisements are shown and will work with the ASA “to address any outstanding questions they might have”.

The ASA also found Butlin’s had breached its code by writing to customers that “The big Butlin’s sale ends in four days” and “Time is running out”.

The deadline to participate in the sale was eventually extended by two weeks, which the watchdog said was unfair on those who had been put under pressure to book a break before the initial deadline.

It urged the firm to ensure future promotions are fair to consumers. Butlins said no customers were disadvantaged by the extension of the sale window.

The ASA’s findings come after the Competition and Markets Authority on Tuesday launched a probe into eight companies over potentially misleading online price claims.

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