The operator will occupy the top two floors of Hudson Quarter, a sustainable development which offers more than 11,000 square feet of commercial space.
The site was once the main trunk route for the York and North Midlands Railway and trains to London via Derby and Birmingham, designed in 1840 by George Hudson.
Peter Liney, chief executive of Great Rail Journeys, said the operator wanted to invest in a "more flexible, creative and collaborative" environment.
"With almost direct access to the main train station, we hope to encourage the very best talent the industry has to offer with people benefitting from the great commuter links," he added.
"As a business in the travel industry rebuilding after the hard-hitting pandemic, being able to deliver our expertise from a reimagined space has also assisted us in reducing our office footprint by 40%."
