The following links and documents include important information about U.S. Postal Service Regulations related to centralized mailbox requirements and standards:
New Construction Development Centralized Mail Center Planning: USPS Delivery Planning Guide for Builders and Developers
(Please note that the USPS updates standards and information periodically. Always check with your local Postmaster before proceeding with mail center projects.)
Renovations/Remodel Projects Guide to Mailbox Planning: Postal Operations Manual Section 6 – Delivery Services
(See 632.621 – USPS requires mailboxes to be upgraded to currently approved standards when any remodeling or renovation occurs to the property)
Contact Local Postmaster to Review Centralized Mailbox Project Plans: Find Your Local Post Office
(Always explain you are looking for centralized mailbox planning guidance when contacting your Post Office as personnel assigned may vary.)
Find USPS Approved Mailboxes and Approved Manufacturers: Postal Bulletin - May 2023 (full document)
(Some product changes and approvals may not be reflected in current Bulletin as the Postal Service publishes this document annually.)
USPS Regulations Governing Centralized Mailbox
Cluster Box Unit Installation Planning for Accessibility: APPENDIX - National Delivery Planning Standards - A Guide for Builders and Developers
(See important information regarding customer and carrier accessibility and plan your CBU installation according to USPS standards.)
Obsolete NDCBU Not Approved for Use – Replace with Current CBU Model: See current Postal Bulletin – Cluster Box Units Section
(NDCBUs are no longer supported for any continued centralized mail delivery service. All reasonable efforts must be made to identify all NDCBUs still in service and get them replaced as quickly as possible.)
USPS Published Standards for Wall-Mounted Centralized Mailbox Receptacles: STD-4C Federal Register Rules and Regulations
(The Federal Register is not regularly updated – refer to the Postal Operations Manual and National Delivery Planning Standards Guide published by the USPS for current regulations for planning your mail center.)
USPS Requires (1) Parcel Locker for every (5) Mailboxes (1:5) – refer to Postal Publications linked below: