In a statement released today the travel giant said Flintham would take responsibility for the day-to-day operations in the UK from March 2018.
Former UK managing director Chris Mottershead has been appointed chief of UK source market and group differentiated product.
Cook said the move would see Mottershead taking responsibility for the relationship with Thomas Cook Group’s "most important partners and hotel procurement, along with the service and experience that customers enjoy in those hotels when in resort".
Flintham, who was most recently as commercial director for Tui UK and Ireland, began his career in travel with British Airways in 1998. He will report directly into Mottershead, who will retain overall responsibility for the UK source market alongside his new responsibilities, Cook said.
Flintham said: "I’m very excited to be joining Thomas Cook to lead the UK business at such an interesting time for the tour operating industry. Their customer at our heart strategy is a great proposition - I am looking forward to next year."