The operator said it was seeking to capture a larger slice of the US $100 billion a year global touring market by targeting growth in "existing and untapped" customer segments.
It will initially be rolled out in Belgium before launching on an international basis this year and into 2024.
Tui said the new digital platform would simplify development for both agents and consumers of multi-day tours and roundtrips across group and individual tours.
Since 2018, Tui claims to have provided tours for more than 500,000 customers, but plans to grow this significantly by shaking up the "largely offline and highly fragmented" touring sector.
Developed in partnership with travel tech start-up Nezasa, Tui Tours features drag and drop functionality and provides live pricing.
Agents and customers can select from group or individual itineraries and then personalise them using both Tui and third-party components, including flights, accommodation, transfers, car rental, experiences and guides.
It also allows them to package Tui exclusive products from its Robinson, Magic Life and Tui Blue portfolios, and Tui Collection experiences.
Peter Krueger, Tui chief strategy officer and chief executive of holiday experiences, said growing the group’s experience product portfolio was a "key strategic priority".
"The tours segment, in particular, is a sizeable and strongly growing market. We are proud having successfully launched a new fully integrated platform."
David Burling, chief executive Tui markets and airlines, added: "We are bringing something totally new to the market – scalable customisation of tours.”
The platform spans already available individual and group touring options in 30 countries across Africa, Asia-Pacific, Europe and the Americas, and replaces previous local solutions.