Area Distribution Center
A USPS facility that consolidates and distributes mail within a geographic region, operating between Network Distribution Centers and local post offices in the processing hierarchy.
Area Distribution Centers (ADCs) occupy a middle tier in the USPS network, typically serving a metropolitan area or a cluster of SCFs. They receive mail from NDCs and sort it for onward dispatch to individual SCFs or, in some cases, directly to delivery units.
The USPS has been consolidating ADC and SCF operations as part of its Delivering for America strategic plan. Some ADCs have been repurposed as Regional Processing and Distribution Centers (RPDCs), larger facilities designed to handle both packages and letter mail under one roof.
For mailers, the ADC level matters primarily for presort discounts: mail sorted to the ADC level (grouping ZIP codes served by the same ADC) qualifies for lower rates than unsorted mail but higher rates than SCF-level presort.