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All Indoor Mailboxes

Shop Indoor Mailboxes

Indoor mailboxes ensure mail for multi-family residences and universities are kept safe and secure. With durable construction, these USPS-approved locking indoor mailboxes can be used in many locations for reliable mail service.

60 Door Private Use Rear-Loading Cluster Mailboxes

Rear-loading Private Use Horizontal Mailboxes – 60 Doors



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Shop for Indoor Mailboxes Online from US Mail Supply

US Mail Supply provides you with replacement and private use indoor mailbox solutions for multi-tenant locations, commercial buildings, and institutions. We have a range of options, including horizontal mailboxes, vertical mailboxes, and custom or private use horizontal mailboxes. Please call us if we can help point you in the right direction.

View all available mailboxes for sale from U.S. Mail Supply.

Safe and Secure Indoor MailboxesIndoor Mailboxes for Sale Online

We are sure to have the right indoor mailbox for you no matter what your situation. From a small apartment building to an entire university, hospital or military base, we make sure everyone has a place to receive their mail in a space-conscious, efficient and convenient way.

U.S. Mail Supply builds all our indoor mailboxes with aluminum and stainless steel and with the option of either rear loading or front loading, depending on your application or preference. We adhere to the US Postal Service's high standards and design our mailboxes for security and vandal resistance. We offer a huge variety of apartment mailboxes for sale for multi-family residences across the United States - from indoor horizontal mailboxes to outdoor cluster boxes.

Horizontal Lockable Indoor Mail Boxes for Multi-Family Residences and Universities

Its rugged construction and heavy build make the USPS-approved Horizontal Mail Boxes ideal for many locations. These high-security mailboxes provide tenants with reliable and safe mail service.

Fully-Customizable Mail Supplies

Customize your tenants’ mailbox with three number decals or engrave up to six characters for identification. Choose from either bronze or aluminum powder coat finishes. These horizontal mailboxes are used for indoor use only. Documents and dimensions for installation can be found on our product page.

Vertical Lockable Indoor Mail Boxes for Residential and Commercial Use

The Vertical Mailbox is the perfect mailbox for tenants. These are corrosion resistant and rustproof to increase the service life of the mailbox. All indoor commercial mailbox units are available in the original aluminum silver finish. We also offer these powder coated finishes:

  • Brass
  • Bronze
  • Sandstone
  • Green

This mailbox comes with one name cardholder per door for tenant identification. There are two installation options— recess mount or surface mount. You can count on highly-secure mailboxes for your tenants no matter which mounting method you choose.

Contact U.S. Mail Supply today at 262.782.6510 or 800.571.0147 for more information.
Make sure to choose the RIGHT mailbox.

Don't worry, we can help you figure out what's best and most cost efficient for your space. A representative at U.S. Mail Supply will help you figure out what is required for USPS or private delivery, the number of units you need and any information required for installation.