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How do I install multi-unit mailboxes?

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Installation is very straightforward for these multi-unit mailboxes and is very similar to the process used to install a single-family, curbside mailbox. Below are some basic steps you’ll need to follow to ensure that your mailbox will receive USPS delivery.

  1. Choose the correct spot. Start by choosing a place six to eight inches away from the curb. If you don’t have a curb, you’ll want to contact your postmaster to ensure you’ve chosen the correct place.
  2. Mount your post, or posts.
    • You’ll need to dig a hole between a foot and two feet deep (12 inches to 24 inches.)
    • A post hole digger will be very helpful for this task.
    • Avoid placing your mailbox in an unstable support, such as in a milk jug filled with concrete. These supports could be dangerous to drivers of a car were to hit them, as mailbox posts are meant to bend or fall away on vehicle impact.
    • Once your post (or posts) are at the correct depth, and you’ve ensured your mailbox will be no higher than 42 inches from the ground (not the road), fill in the hole.  Also be sure that the mailbox itself is between 41 and 45 inches above the road.
    • Fill in the hole(s) or pour concrete up to a few inches from the ground’s surface. Adjust the mailbox if necessary.
    • Allow the concrete to dry before covering with dirt.
  1. Mount your mailboxes.
    • Follow the manufacturer’s directions for mounting your mailboxes. Each type is different.
  1. Add the address.
    • Ensure each letter and number is at least one inch high. You can skip this step if you’ve ordered address plaques with your mailboxes.
    • If the mailboxes are on a different street than their corresponding homes or offices, you must put the full street address on the box.