A method and corresponding equipment to enable a phone owner, who desires to lend a phone to a borrower, to define a temporary limit for the usage of the borrower, especially in a prepaid charging system. The charging system uses this temporary limit to restrict service usage such that when an amount corresponding to the temporary limit has been spent service is denied until such time as the limit has expired or been withdrawn, even if, for example, there is still a positive balance in the phone owner's own prepaid account.