The Belgian's current £100,000-a-week deal at Stamford Bridge, which runs out at the end of next season, will be extended until 2023, according to 'The Telegraph'.
The deal, including bonuses, would be worth over £200,000 a week, therefore overtaking Manchester United's David De Gea as the world's highest-paid goalkeeper.
The Belgian has been a long-term target for Spanish giants Real Madrid, and he even expressed his desire to return to the Spanish capital to be with his two young children.
With Madrid focusing on Athletic Bilbao stopper Kepa Arrizabalaga and Chelsea cooling interest in reported target Jack Butland from Stoke, Courtois looks set to stay in west London.