Apartment Mailboxes - USPS Approved, Multi-unit & Secure

Apartment Mailboxes for Multi-Tenant Buildings

Apartment mailboxes provide a secure and centralized mail delivery system for apartments, condos, student housing, and mixed-use buildings. Many of the units available on this page are USPS-approved, and the product listings indicate which models meet current postal requirements. Several options are also suitable for indoor or outdoor installation, depending on the model.

These mailboxes are built from heavy-duty aluminum and include high-security tenant locks, multiple color options, and durable hardware. Several of the USPS-approved models on this page are manufactured by Florence Corporation, a company with more than 85 years of experience producing secure and reliable mailbox systems. Many models also include parcel lockers to support the growing volume of packages in multi-tenant communities.

Types of Apartment Mailboxes We Offer

We provide USPS-approved mailbox solutions for new construction, remodels, and replacement projects. Here is a quick overview of the options available on this page:

Cluster Box Units (CBU) for Outdoor Apartment Mailboxes

Cluster Box Units are one of the most common choices for outdoor apartment mailbox systems. They are placed in central delivery areas such as parking lots, clubhouse entrances, and community common spaces.

Here is a quick look at what CBUs offer:

• Secure tenant compartments for everyday mail

• Integrated parcel lockers for packages

• A pedestal base for long-term stability

• USPS-approved construction suitable for outdoor use

• A cost-effective price per tenant mailbox, especially in larger communities

4C Horizontal Apartment Mailboxes for Lobbies and Kiosks

4C mailboxes are the current USPS required standard for new multi-tenant construction and most remodel projects. They are available in recessed and surface mount configurations, making them suitable for lobbies, hallways, and indoor mail rooms.

Here is what 4C systems typically include:

• Integrated parcel lockers to support package delivery

• Multiple module heights to fit different installation needs

• Flexible layout options for lobby or wall-mounted configurations

• Full compliance with USPS STD 4C requirements

• ADA-compliant 4C mailbox configurations are also available for properties that need accessible tenant compartments.

4B+ Horizontal Mailboxes for Replacement Projects

4B+ horizontal units are designed for replacement projects only. They are not approved for new construction, but they are ideal for properties that want to keep an existing wall opening while upgrading to a more secure system.

Local USPS approval is still required during replacement. These units help older properties maintain compliance while reducing the need for major renovations.

Decorative Apartment Mailboxes for High-End Communities

Decorative CBUs offer a more polished appearance for communities that want it. They are a good fit for luxury apartments, gated communities, and properties seeking mailbox stations that coordinate with their architecture.

Here are some decorative features available:

• Decorative pedestals that add visual height and presence

• Classic cap styles for a traditional look

• Trim enhancements that give the unit a finished appearance

These models maintain full USPS approval and provide the same level of security and durability as standard CBUs.

Private Delivery Mailboxes for Campuses and Corporate Housing

Some properties use mailbox systems that do not require USPS access. These private delivery models allow an on-site staff member to sort and distribute mail internally. Since they are not used for USPS delivery, they offer more flexibility in configuration and placement.

These mailbox systems work well in locations such as:

• Campus housing

• Corporate housing

• Military bases

• Offices or communities with internal mail operations

How to Choose the Right Apartment Mailbox System

Choosing the right mailbox system starts with understanding your property type, tenant count, delivery method, and long-term parcel needs. Here is a simple guide to help you move in the right direction.

Start with Your Property Type and Tenant Count

Choosing a mailbox system often depends on how many tenants you have and the type of building you manage.

Here is a quick breakdown to help narrow your choices:

• Smaller existing buildings often use 4B+ horizontal units when replacing older wall-mounted systems.

• Some older properties may still use vertical mailbox units when updating legacy installations.

• Larger or new communities benefit from recessed 4C horizontal units indoors or CBUs outdoors.

• Properties with multiple buildings may need more than one mailbox station to support tenant access.

Decide on Indoor vs Outdoor Apartment Mailboxes

Your installation location will guide whether you need an indoor or outdoor mailbox system. Here is a quick overview of the options available for each setting:

Indoor options include:

• Recessed or surface-mounted 4C mailboxes.

• 4B+ horizontal replacement units

• Lobby or hallway mailbox kiosks

Outdoor options include:

• Standard CBUs

• Decorative CBUs for communities that want upgraded styling

• Covered mailbox kiosks that offer added weather protection

Even when certain 4C mailbox configurations are approved for outdoor use, adding a protective structure is recommended to improve long-term durability and tenant comfort.

USPS Delivery vs Private Delivery

Your mailbox choice depends on whether mail is delivered by the USPS or by an on-site staff member.

Here is a quick overview of how each option works:

• USPS delivery requires USPS-approved products such as CBUs, 4C units, or 4B+ units for replacement projects. These models meet current postal standards for secure access and compartment sizing.

• Private delivery is used when a staff member distributes mail internally. These mailbox systems offer more flexibility because USPS standards do not apply, and they can be placed wherever internal operations allow.

Plan for Parcels and Future Growth

Package volume continues to increase in many communities. USPS recommends at least one parcel locker for every ten tenant compartments. Properties with higher package traffic may need more.

Planning ahead helps reduce the need for future expansion and supports a smoother delivery process for residents.

Balance Security, Aesthetics, and Budget

Each mailbox type offers strengths that match different property needs.

• Standard CBUs offer strong security, durable powder-coat finishes, and tamper-resistant locks.

• Decorative CBUs improve curb appeal while offering the same durability and USPS approval as standard models.

• 4C units create a clean, modern look indoors and support secure tenant access with integrated parcel options.

Choose the option that fits your property’s style, long-term needs, and available budget.

USPS Approved Apartment Mailboxes and Compliance

The mailbox systems shown on this page are USPS-approved where indicated. They meet current USPS standards, including STD 4C for new construction and STD 4B+ for replacement of existing wall-mounted units. These models are manufactured to meet the full USPS-STD-4C and USPS-STD-4B+ specifications.

The local postmaster must approve the exact placement and configuration before installation. If you need help preparing layouts or confirming compliance, our team can guide you through the process and help coordinate the details required by USPS.

Installation and Delivery

Here is what you can expect when preparing for installation:

• Installation is usually handled by a contractor, maintenance team, or facilities staff familiar with mounting and anchoring requirements.

• CBUs include pedestals, tenant locks and keys, and factory preparation for the USPS master lock.

• Horizontal mailbox units include mounting hardware when applicable.

• Delivery times vary by model. Most products show expected ship times in their product listings.

• The USPS installer will add the postal master lock to USPS access doors during the final setup.

Not sure where to start? Our team can help you design a compliant apartment mailbox layout for your property. You can reach us at (866) 214-0017 for support with planning, placement, and USPS approval.

What is the difference between 4C mailboxes, 4B+ horizontals, and CBU cluster box units?

Here is a simple way to understand how these three mailbox types differ:

• 4C mailboxes: Required for new multi-tenant construction. They are recessed or surface-mounted units used in indoor areas such as lobbies, hallways, or mail rooms. They include parcel lockers and meet current USPS STD 4C standards.
• 4B+ horizontal mailboxes: Used only for replacement projects where an older wall opening already exists. They provide improved security but are not approved for new construction.
• Cluster Box Units (CBUs): Outdoor, pedestal-mounted mailbox systems that include tenant compartments and parcel lockers. They are USPS-approved for centralized outdoor delivery and are often the most cost-effective option.

Can I mix different apartment mailbox types on the same property?

Yes. Many properties use a combination of mailbox types depending on layout and tenant needs. For example:

• A community may install CBUs outdoors near parking areas
• And use 4C mailboxes indoors for lobby delivery

The important part is confirming that any mailbox used for USPS delivery meets the required postal standards. If you are planning a mixed layout, our team can guide you on what options work best for your property.

 

Who installs the apartment mailboxes and the USPS master lock?

Mailbox installation is usually handled by a:

• contractor,
• facilities team, or
• maintenance staff member

Most mailbox units arrive with tenant locks, keys, mounting hardware, and installation instructions. After installation, the USPS will install the postal master lock on any compartment that requires USPS access. This is done by your local post office once they approve the location and setup.

How long does it take to receive my apartment mailboxes after I order?

Shipping times vary by model and manufacturer. Each product listing includes the most accurate estimate of when the item will ship. In general:

• Standard CBUs tend to ship faster
• 4C and 4B+ units with custom configurations may take longer

If you are working within a project timeline, we can help you choose options that match your schedule.

 

Can I use these mailboxes for internal or private delivery only?

Yes. Private delivery mailboxes are designed for properties where an on site staff member handles mail distribution. These systems:

• do not require USPS approval,
• can be placed in any convenient location, and
• offer more flexibility in setup and configuration

They work well for corporate housing, campus housing, military bases, and other communities with internal mail operations.