Travelzoo has been ordered not to mislead consumers about the length of holidays.
The advertising watchdog upheld a complaint over an advert promoting a three-night Ibiza break for £99 which involved travel on the first and third nights.
The Advertising Standards Authority acted after receiving a complaint about the holiday based at the Tropical Hotel in San Antonio.
The flight times meant that the holidaymaker arrived at Ibiza airport at 1.35am on the first night and departed at 1.45am on the third night.
The ASA, banning the advert, said: “We considered that some of the flight times, including those of the complainant, did not accord with consumer expectations of a three-day holiday because passengers on those flights only had one full night at the hotel.
“We therefore concluded that the claims ‘this 3 night Balearic break’ and ‘three nights at the Tropical Hotel’ had not been substantiated and were misleading.”
In a statement Travelzoo said: “This is the first time since we started publishing deals in the UK in 2005 that we have had this sort of ruling against us from the ASA and we take it very seriously.
“We pride ourselves on the fact that we research, test and evaluate over 120,000 deals a year. On this occasion one of the variations of the multiple departure and return flight options meant that this particular booking did not have three full nights in a hotel as the customer arrived after and departed just after midnight on the first and last nights.
“The majority of the flight times that we tested for this Ibiza deal had three full nights in the hotel in Ibiza and we will work hard to ensure that this sort of one-off anomaly does not happen again.”