carrier route

Households served by an individual mail carrier within a five-digit zip code area. The carrier route is used to divide mailing lists into segments. Mail presorted by the mailer according to carrier route before entry into the postal system earns a substantial postage discount. The number of households within a carrier route ranges from 100 to more than 2500, based on whether the carrier serves a high-density area, such as an apartment building, or a low-density rural area. There are approximately 570,000 carrier routes in the United States. See also address coding guide; carrier route coding; carrier route information system; carrier route presort; carrier route qualified; list enhancement; list segment.