Post Mount Mailboxes FAQ

What is a residential post-mount mailbox?

Designed for roadside mail delivery and known as a “curbside” mailbox, this is the most common setup. You can choose locking or non-locking, and mount on a post set in the ground or set in concrete. You may also bolt some curbside mailbox posts to a concrete base.

How deep does the mailbox post have to be in the ground?

As a general rule, installers should dig the hole for your mailbox post at least 20 inches deep. You can use fast set concrete to help make the post more secure. In some cases, installers can bolt mailbox posts to a pre-formed concrete base.

What is a column insert mailbox?

Column mailboxes are also generally designed for roadside (curbside) mail delivery. Instead of mounting on a post, you would install the locking or non-locking mailbox insert within a pre-built or custom-built masonry column.

Does it matter which side of the road I place my post mount mailbox?

As a general rule, you should install a residential post mount mailbox on the same side of the street as the delivery address. You could also install your post on the opposite side of the road if that is in keeping with the mail delivery route’s direction. Contact your local Post Office for more info, if needed.

How far does a mailbox have to be in from the road?

When installed, your post mount mailbox’s door should be no more than 6 to 8 inches away from the curb.

How high does a mailbox have to be from the surface of the road?

Install your post mount mailbox so that the mailbox’s bottom surface is within 41 to 45 inches from the road’s surface. Visit this USPS Mailbox Guidelines page for information on installing a new mailbox.

Does a residential mailbox need to have the full home address on it?

We recommend showing your address numbers on the mailbox or post. Adding an address is helpful; add your full home address if you intend to install your mailbox on the street’s opposite side.

How big does the mailbox address have to be?

Your mailbox address numbers should be at least 1 inch tall.

Where on the residential mailbox should the address be located?

In general, you should install your address numbers on the front door and on the same side as the mailbox flag.

How much does a mailbox post cost?

Mailbox post prices can vary quite a bit depending on the type of mailbox post you need, how you plan to install it, and whether you install it yourself or not. Wooden mailbox posts can be less expensive, and often homeowners prefer to install these posts in the ground. In contrast, metal and aluminum mailbox posts may cost more, and owners tend to bolt these posts onto a concrete pad.

Does a mailbox post need concrete?

Yes. Pouring concrete into the post hole will help secure an in-ground mailbox post and protect wooden posts from rot. Above ground metal and aluminum mailbox posts are generally bolted to a concrete pad pre-set with anchor bolts.