The following documents include important information about Postal Regulations and mailbox design standards:
UNITED STATES
New Development Mail Delivery Planning Resources from the U.S. Postal Service
USPS Delivery Planning Guide for Builders and Developers (.pdf)
Find Your Local USPS Delivery Growth Management Coordinator
USPS Approved Mailboxes
The following documents include lists of USPS Approved products and their manufacturers:
Postal Bulletin - May 2020 (full document)
Postal Bulletin - May 2019 (full document)
USPS Approved Mailbox Products 2018-2019(all)
USPS Approved Cluster Box Unit Products 2018 - 2019
USPS Approved Std-4C Mailbox Products 2018 - 2019
USPS Approved Horizontal Mailbox Products 2018-2019
USPS Regulations Governing Wall-Mounted Centralized Mailboxes
STD-4C Federal Register Rules and Regulations
U.S. Postal Service Standard Wall-Mounted Centralized Mail Receptacles
July 2020 - USPS Updated Mailbox to Parcel Locker Ratio Requirements to 5:1 (see pg. 13)
FAQ - Choosing a USPS-Compliant Replacement Mailbox
USPS Regulations Governing Pedestal-Mounted Cluster Mailboxes
Neighborhood Delivery Collection Box Units (NDCBU) Not Approved for Replacement
Cluster Box Unit Installation Planning - Siting for Accessibility and Maneuvering Space
CANADA