Systems, mechanisms, and methods are described that relate to the production of a custom printed insert(s) that can be custom printed prior to insertion of the custom printed insert(s) into an envelope along with a personalized card/carrier combination for mailing to the intended holder of the personalized card. The inserts are custom printed using an insert printer that is located in the inserter mechanism that is used to insert the insert(s) and the card/carrier combination into an envelope for mailing to an end user of the card. The inserter mechanism can have an “off-line” configuration, i.e. configured as a stand-alone mechanism, or configured for “in-line” use, i.e. used together with other mechanisms.