Systems and methods are provided for assigning mail items to carriers, comprising at least one server containing a mail assignment engine. The mail assignment engine is operative to receive delivery data from the mail processors, determine routes for delivery using the delivery data and a set of business rules, assign the mail items to carriers based on the determined routes, and transmit mail item assignment information to the mail processors. The mail assignment engine may determine the routes using a database including files for active, planned, and closed routes. The mail assignment engine may also use business rules, which may comprise cost consideration, delivery options, and route delay information.