customer base
US /ˈkʌs.tə.mər ˌbeɪs/
UK /ˈkʌs.tə.mər ˌbeɪs/

1.
clientèle, base de clients
the group of people who regularly buy from a particular shop or business
:
•
The company is trying to expand its customer base.
L'entreprise essaie d'élargir sa clientèle.
•
A loyal customer base is essential for long-term success.
Une clientèle fidèle est essentielle pour un succès à long terme.