4B Horizontal Mailboxes

Budget Mailboxes is proud to supply durable, secure 4B horizontal mailbox units in several configurations for replacement of your existing mailbox system.

Key notes about the USPS 4B Mailbox:

• Due to a 2006 updated USPS ruling, the 4C is the current requirement for all new construction projects.
• You may continue to use a 4B configuration after a renovation, provided the mailbox housing or wall opening does not change.
• Our 4B horizontal mailboxes are available in multiple door sizes with various options of individual box quantities to fit your exact specifications.
• Made of durable aluminum construction with stainless steel locks and hinges, these units are engineered to provide years of service.

As previously mentioned, the USPS mandates that the 4B mailbox is no longer acceptable for new construction. These mailboxes are available only as replacement units for existing 4B applications where USPS delivery is required. For a complete list of commercial mailboxes click here.

The 4C mailbox is the most current USPS standard for all new construction applications. If the opening dimensions for the cluster housing is modified in any way, then the 4B must be upgraded to a 4C CBU. If you intend to use the 4B horizontal for USPS delivery, then we encourage you to contact your local postmaster to verify authorized use before placing your order.

Note: 4B horizontal mailbox installations should be protected from direct exposure to the weather. The manufacturer is not responsible for damage caused by weather conditions as these products are rated for indoor use only.

If your project requires installing a 4C mailbox, please view our 4C horizontal category page. To view other commercial mailboxes, click here.

What is Standard USPS 4C?

The United States Postal Service expanded the width of mailbox compartments and answered the demand for more secure delivery with a new standard, USPS 4C. What does this mean?

• This standard replaces the traditional, cube style compartments with more flat style compartments and incorporates integrated or stand-alone parcel locker options.
• A minimum of one parcel locker is required for every ten tenant compartments.
• Parcel lockers are not required in installation sites with less than ten tenant compartments.
• This standard requires that 4C horizontal mailboxes and parcel lockers be installed in all new construction projects and major remodels effective October 2006.

What is Standard USPS 4B+?

The demand for improved mailbox security prompted the United States Postal Service to develop this standard. Some key notes to remember:

• This standard requires manufacturers to strengthen and improve the master door (arrow lock compartment) on horizontal style mail receptacles.
• Our 4B horizontal mailboxes are USPS approved and in full compliance with the requirements of USPS 4B+.
• These 4B+ horizontal mailboxes are approved for replacement and/or retrofit installations effective October 2006.
• For new construction or major remodels (if the housing dimensions are modified), 4C horizontal mailboxes are required.