A vital part of the mailing process involves the implementation of streamlined and efficient operational procedures. This section contains information on the latest USPS compliance standards, processes, facilities, and equipment. 


Mail Preparation

Labeling Lists

The Labeling Lists Data Product assists mailers with presorting mail by providing active, originating 3- and 5-digit ZIP Code™ data, along with their destination locations, for labeling purposes. 

Please click here for a directory of all labeling list files.

Flats Sequencing System

The USPS® is deploying a new technology that will boost efficiencies in the processing, distribution, and delivery of flats–the Flats Sequencing System (FSS). FSS will automatically sort flat-sized mail into delivery point sequence at high speeds. The efficiencies gained by employing FSS are influencing many changes within both the Postal Service® and the mailing industry.

Product Classification

Category B Infectious Substances

Infectious substance means a material known or reasonably expected to contain a pathogen. A pathogen is a microorganism that can cause disease in humans or animals. Examples of pathogens include bacteria, viruses, fungi, and other infectious agents. An infectious substance must be assigned to one of the following two packaging categories:

Cigarettes, Smokeless Tobacco, and Electronic Nicotine Delivery Systems (ENDS)

Cigarettes, Smokeless Tobacco, and Electronic Nicotine Delivery Systems (ENDS) are generally non-mailable, unless authorized by an exception, if all PACT ACT related conditions of mailability are met. 


Please click here to view the final Federal Register Notice regarding the treatment of e-cigarettes in the mail.


Please click here to view the Postal Bulletin regarding Publication 52 Revision: Cigarettes, Smokeless Tobacco, and Electronic Nicotine Delivery Systems

Polywrap and Polywrap Manufacturers

Manufacturers and mailers of flat-size mail must comply with USPS-T-3204, which went into effect February 4, 2007. In 2006, the USPS conducted a thorough study of automatable polywrap films to ensure compatability of automation flats with flats sequencing systems (FSS) and stand alone mail prep (SAMP) according to standards AFSM 100 and UFSM 1000.

Sharps and Regulated Medical Waste

Regulated medical waste and sharps medical waste as defined in 346.12f and 346.12g and containing materials classified as Category B infectious substances are permitted for mailing provided that all applicable requirements specified in 346.322 are met. For packaging instructions for medical professional packages, refer to 346.322bd.

Toy Propellant Devices

The proper shipping name for a mailable toy propellant device is “model rocket motor” or “igniter.” A device that is assigned identification number NA0323 or UN0454 and classed as a Division 1.4S explosive is eligible for mailing in domestic mail via surface transportation only, provided that all requirements are met and the device is properly package. See specifications in 341.22a.

USPS® Container Requirements for Adult Birds

Disease-free adult birds may be mailed domestically when shipped under all applicable governmental laws and regulations, including the Lacey Act, the Endangered Species Act (ESA), and regulations of the U.S. Department of Agriculture, U.S. Fish and Wildlife Service, and any state, municipal, or local ordinances.


Drop Shipment Management System (DSMS)

The Drop Shipment Management System (DSMS) program allows authorized users to streamline the Plant-Verified Drop Shipment (PVDS) process through consolidating PVDS documentation from multiple jobs and mailing locations in electronic files. 



Facility Access and Shipment Tracking (FAST®)

The Facility Access and Shipment Tracking (FAST®) system allows mailers to provide advanced notification of drop shipment and origin entered mailings into postal facilities. FAST provides business mail owners, preparers, and schedulers enhanced visibility of their scheduled mailings at each facility. To make an appointment, log in to your FAST account.

Service Hubs and Facilities

The general role of Hubs in the current network will be to serve as down-flow mail facilities similar to our Network Distribution Centers (NDCs), Area Distribution Centers (ADCs) and Sectional Center Facilities (SCFs). If a facility is identified as a Hub, it will serve as a cross-dock facility for destinating volume that is properly prepared and entered at the Hub location. The Hub will transport mail to the downstream delivery units that the Hub services.