Meaning of “pay-as-you-go” - Learner’s Dictionary

pay-as-you-go

adjective [ always before noun ] uk us /ˌpeɪəzjəˈɡəʊ/

describes a system in which you pay for a service before you use it:

a pay-as-you-go mobile phone
pay-as-you-go noun [ U ]

(Definition of “pay-as-you-go” from the Cambridge Learner’s Dictionary © Cambridge University Press)