The requirement, which expands on a policy implemented earlier this year on its European itineraries, came into effect on Tuesday (7 September).
According to Jeremy Palmer, Tauck’s senior vice president of worldwide operations, the move comes as country’s entry requirements "evolve rapidly".
"We’re seeing a steady increase in restaurants, museums and attractions requiring proof of vaccination, to the point where unvaccinated travelers won’t be able to fully participate in their Tauck journeys," he added.
"It’s become clear that a universal vaccination requirement is the best way to ensure our guests enjoy all of the incredible experiences we build into our tours and cruises.”
Over the past few months Tauck has hosted thousands of guests on more than 80 itineraries. Palmer anticipated that the company’s customers – 97% of whom are reportedly already vaccinated – would "appreciate the simplicity" of the new policy.
Guests who are impacted by the policy change can utilise Tauck’s flexible booking policy, which waives all change penalties when a customer’s booking is transferred to another Tauck trip operating in 2021 or 2022.