Postal Regulations / References

Postal Regulations/Standards

The following documents include important information about Postal Regulations and mailbox design standards:


STD-4C USPS Specification Overview

STD-4C Federal Register Rules and Regulations

STD-4B USPS Standards (superseded by STD-4C)


Canada Post Mailbox Regulations

Canada Post Delivery Planning Standards


USPS Approved Products

The following documents include lists of USPS Approved products and their manufacturers:

Postal Bulletin - May 2016 (full document)

          USPS Approved Mailbox Products 2016-2017(all)

                    USPS Approved Cluster Box Unit Products 2016 - 2017

                    USPS Approved Std-4C Mailbox Products 2016 - 2017

                    USPS Approved Horizontal Mailbox Products 2016-2017

USPS Approved Mail Receptacles List


Postal References

The following documents include additional Postal References for USPS Delivery:

STD-4C Quick Reference and Accessibility Guide

STD-4B+ and STD-4C Selection Guide


Postal Locator

The following US Postal Service website will aide in searching for local postal authorities:

USPS Locator

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