Cook will transfer around 3,000 hotel contracts from across the group to Sunhotels - Webjet’s European online accommodation business.
The agreement builds on a partnership Sunhotels already has with Thomas Cook in its Nordic markets.
The contracts will be added to Sunhotels’ existing inventory of 75,000 hotels worldwide, which will also be offered to Thomas Cook.
Thomas Cook said the partnership will allow it to focus on growing its “core differentiated holiday offering” while “providing customers with a wider range and choice of complementary hotels in a more efficient way”.