The minimum requirement to apply for a Chevening Scholarship is:

IELTS 6.5 (with a minimum score in each component of Listening - 5.5; Reading - 5.5, Speaking - 5.5, Writing - 5.5)
Pearson PTE Academic 58 (with a minimum score in each component of Listening - 42, Reading - 42, Speaking - 42, Writing - 42)
TOEFL 79 (with a minimum score in each component of Listening - 17, Reading - 18, Speaking - 20, Writing - 17)