The deals publisher earned a 75% customer satisfaction score in the latest research carried out by the influential consumer watchdog.
Which? said the rating this year was based on an assessment of the deals brands offer but also the way they have dealt with the COVID-19 pandemic and demand for refunds.
The organisation said: “The best travel deal websites offer genuine holiday, flight and UK break deals that can save you money, while the worst have poor-value offers and even worse customer service.”
Travelzoo rated highly on factors like choice, transparency, functionality and customer service taking it beyond the threshold to become a recommended provider.
James Clarke, general manager for Travelzoo, said: “We are delighted and very proud to receive this accolade this from Which?.
“Our members’ experience, whether it’s on a deal or from our customer service, is what drives our brand.
“Recognition like this from such an esteemed and well-respected publication is a testament to the hard work our team puts into both delivering the very best content, and making sure our members get whatever peace of mind we can provide over this period of uncertainty.”
Which? also assessed Secret Escapes and lastminute.com in the travel deals websites category the former of which was marked down due to coronavirus refunds and the latter was named the worst site.