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Commercial Building Mailboxes


More Info About Commercial Building Mailboxes

Salsbury Industries offers a complete line of quality mailboxes for commercial buildings. These mailboxes are available for new installations, and retrofit and replacement applications. Most commercial mailbox units are in stock and ship within a few days. Products include cluster mailboxes, 4C horizontal mailboxes, 4B horizontal mailboxes, 4B vertical mailboxes and courier boxes.




Indoor Mailboxes for Commercial Buildings


4C horizontal mailboxes are the most popular indoor mailbox used in commercial buildings. Unlike pedestal mounted mailboxes such as the cluster mailbox unit, 3700 series 4C horizontal mailboxes are typically recessed into the wall. Available in aluminum, bronze, sandstone and black, 4C horizontal mailboxes are made of heavy-duty aluminum with stainless steel hardware and are ideal for office buildings, hotels, apartment complexes, government offices, universities, medical centers and other commercial developments. Salsbury Industries offers 4C horizontal mailboxes in recessed mounted, surface mounted and free-standing models.






Outdoor Mailboxes for Commercial Buildings


The 3300 series cluster box unit (CBU) is a free-standing mailbox option for commercial buildings. Cluster mailboxes are USPS approved and are ideal for office complexes, industrial buildings, medical centers, hotels, retail stores, multifamily housing locations, warehouses and other commercial applications. 


These units are extremely secure with heavy-duty cam locks and anti-fish plates to prevent mail tampering. CBUs include a pedestal and are available in 4, 8, 12, 13, and 16 mailbox door configurations (plus parcel lockers for package delivery).  Designed with elegance in mind, Salsbury Industries also offers regency decorative cluster mailboxes that come with a decorative top and decorative pedestal cover. Cluster box units are available in sandstone, bronze, white, green, black and gray.







Other Mailboxes for Commercial Buildings


Designed for replacement and retrofit installations, Salsbury 4B horizontal style commercial mailboxes are another commonly used wall mounted commercial building mailbox. Available as a recessed mounted unit, the Salsbury 4B horizontal style mailbox is made entirely of aluminum and available in 3 colors – aluminum, bronze and sandstone. 4B mailboxes are also available as vertical units that come in 3-door, 4-door, 5-door, 6-door, and 7-door configurations. The 4B vertical mailboxes can be purchased as recessed mounted or surface mounted units and are also available in aluminum, bronze and sandstone colors. 






USPS Mailbox Requirements for Commercial Buildings


USPS commercial mailbox requirements dictate that all new construction and major renovations must meet current USPS specifications. Commercial mailboxes for U.S.P.S. delivery include cluster box units (CBUs) and 4C horizontal mailboxes. 4B horizontal mailboxes and 4B vertical mailboxes can be used for retrofit applications only. USPS approved mailbox products are commonly used in apartment complexes, commercial buildings, residential developments, condominiums and several other applications.  


4C Recessed Mounted

4B Horizontal

4B Vertical

Cluster Box Units

4C Surface Mounted

4C Free-Standing

Regency® Decorative
Cluster Box Units





Commercial Mailboxes for Sale


Salsbury industries offers a complete line of commercial mailboxes for multi-tenant applications.  Most orders ship within 1 to 2 business days and volume discounts are available. You can order your Salsbury commercial mailboxes via our customer service department or online. If you have any questions about our commercial mailboxes please contact us via email, online chat or toll free at 1-800-624-5269.

FAQ Categories

Questions & Answers

Commercial Building Mailboxes

What is a commercial mailbox?

Commercial mailboxes are mailboxes that are designed to service multiple tenants where the USPS will be delivering the mail to each bank of mailboxes.

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How do you set up a commercial mailbox?

The installation instructions for your commercial mailbox will vary depending on the mailbox system you select. Salsbury Industries includes detailed, easy-to-follow installation instructions with all its mailboxes—just scroll to the bottom of the product page and click “Installation Instructions” under “Downloads”. You can also find installation instructions for commercial mailboxes here.

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What is the largest commercial mailbox?

The Maximum Height Recessed Mounted 4C Horizontal Mailbox with 20 Doors and 2 Parcel Lockers with USPS Access - Front Loading is the largest USPS approved mailbox that Salsbury Industries carries. Check it out here.

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How can my business accommodate packages?

If your business has USPS STD-4C horizontal mailboxes, one parcel locker is required for every five customer compartments. A parcel locker is a lockable unit where mail carriers can leave larger items that won’t fit in a standard mailbox.

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Will the post office deliver to my commercial building?

Yes, the USPS delivers to more than 150 million residential and business addresses daily.

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Do I order 4C or 4B+ mailboxes for my commercial building?

USPS STD-4C horizontal mailboxes are required for new construction and major renovations, while you can only use 4B horizontal and 4B vertical mailboxes for direct one-to-one replacements. If you don’t have to make any changes to the rough opening where the existing wall-mounted mailboxes are currently installed, 4B horizontal or 4B vertical mailboxes can be used (though you should always check with your local Post Office to be sure). Otherwise, 4C horizontal mailboxes must be used. Click here to view information in selecting the right mailbox for your application.

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