System and Method for Validating a Customer Phone Number

The invention relates to a system for validating a pair of phone number and person's name, which comprises: (a) a logical unit at a provider's server which is configured to receive said pair, and to determine based on a number of full matches or partial matches of said pair within as many as possible individual contact lists of respective mobile devices whether the pair is valid or not; and (b) a module within each provider's application which are in turn installed within each of said mobile devices, said module is configured to communicate with the respective contact list stored in the mobile, and to (a) either communicate said full contact list to said provider's server, or (b) to determine whether a full or partial match exists with said pair, and to communicate the determined result to said provider's server.