Abstract: The present invention relates to a communication system comprising a sub-scriber A terminal (MSA), a subscriber B terminal (MSB), a message centre (MC) for transmitting a message from subscriber A to subscriber B on the ba-sis of address data included in the message, and a billing database (31) for maintaining subscriber-specific billing data. The system also comprises means for retrieving information from a third party from a database (DB), means for transmitting said information from a third party to subscriber B in connection with a message sent by subscriber A, and means for adding at least part of the charge incurred by transmitting the message and/or at least part of the cost of the contents of the message to the billing database (31) onto the advertiser's account.