A management system for managing at least one function to be executed in a communication terminal. The management system includes a reception unit that receives identification information about the communication terminal from the communication terminal; a storage unit that stores a service period set for each of functions associated with pieces of identification information about communication terminals; a specification unit that specifies, from the functions associated with the received identification information, functions within the service periods; and a transmission unit that transmits function information indicating the specified functions to the communication terminal.