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A Beginner's Guide to STD-4C Mailboxes

Tuesday December 08, 2020

Mailboxes have evolved over the years. They are no longer limited to traditional curbside designs. While curbside mailboxes are still used, many residences and businesses are now being developed with STD-4C mailboxes. The successor to the United States Postal Service's (USPS's) STD-4B standard, it's a centralized mail delivery system that includes multiple mailbox units. If you're thinking about buying STD-4C mailboxes, though, there are a few things you should about them.

What Are STD-4C Mailboxes?

STD-4C mailboxes are wall-mounted structures consisting of multiple mailbox units that comply with the USPS's STD-4C standard. They don't contain a single mailbox unit. Rather, STD-4C mailboxes are a centralized mail delivery system that contains multiple mailbox units.

Over the past decade, the USPS has been shifting away from curbside mailboxes in favor of centralized mail delivery systems like STD-4C mailboxes. It costs the USPS approximately $224 annually to deliver mail to a single curbside mailbox. In comparison, the USPS only spends about $160 annually when delivering mail to a resident's centralized mail system unit. Along with Cluster Box Units (CBUs), STD-4C mailboxes are one of the most common types of centralized mail delivery systems.

Some of the design specifications for STD-4C mailboxes include the following:

  • One parcel locker per 10 mailbox units
  • Module design
  • Minimum mailbox unit size of 12 inches wide, 15 inches deep and 3 inches tall
  • Mounting and installation hardware must be packaged with STD-4C mailboxes
  • Powder-coated finish to protect against corrosion and degradation
  • Outgoing mail slots
  • Locks and cams for each mailbox unit

STD-4C Mailboxes Now Required For All New Multi-Unit Building Plans

The USPS now requires STD-4C mailboxes for all new multi-unit building plans. What does this mean exactly? New buildings that have multiple residents or tenants must be equipped with STD-C mailboxes. Apartments, for instance, must be designed with STD-4C mailboxes. Commercial offices, assuming they have multiple businesses, must also be designed with STD-4C mailboxes.

It's important to note that STD-C mailboxes can still be used in neighborhoods. Even if a neighborhood doesn't have multi-unit buildings, the USPS allows property developers and managers to use STD-C mailboxes; it's just not a requirement.

Older multi-unit buildings -- those with plans submitted prior to Oct. 6, 2006 -- aren't required to use STD-4 mailboxes, either. Like with neighborhoods, though, you can still use them in older multi-unit buildings. If a building currently has STD-4B mailboxes, you may want to upgrade to the newer and more secure STD-4 standard.


About Forsite:

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Forsite can provide all of your signage needs for your Master Planned Community or  Residential Development. We help our customers to create a uniform, upscale appearance and increase property values by "bundling" themed packages of decorative street signage, mailboxes, post and wall mounted lighting, and wayfinding signage

You can count on the experts at Forsite to help improve the quality of your community today. Contact us today to get started by talking to one of our experienced team members at 855-537-0200.