Provided is a method of reducing postal revenue losses associated with the processing and delivery of international mail pieces. Algorithmically-resolved image data associated with a mail piece is compared to international-mail-services postage data and a determination is rendered, based on the comparison, as to whether any postage indicated as paid is sufficient to further process the mail piece in accordance with the level of delivery service requested. In various aspects, an attempt to algorithmically ascertain the identity of the sender is undertaken for purposes of automated charge assessment relative to a mail piece for which it is determined that insufficient postage has been tendered. In accordance with alternative aspects, if the sender identity cannot be ascertained, the mail piece is variously (i) rejected for manual handling or (ii) routed for automated sortation and delivery in accordance with a "downgraded" delivery service level for which the amount paid is adequate.