How to Install a Mailbox

Instantly boost curb appeal by installing a post or wall-mounted mailbox


Installing a mailbox is a necessary and very simple DIY task for any homeowner. Choose from standard post-mounted mailboxes that line the sidewalk and instantly increase your curb appeal, or a wall-mounted mailbox that can be installed at eye-level on a fence or next to your front door.

This guide will walk you step-by-step through the simple process of both installations. 

The United States Postal Service (USPS) has specific requirements you must follow when installing a mailbox on your property. They are included in this guide, but you can also consult the USPS site here for more details.

Tip: While this guide will provide guidance for typical mailbox installation, there are a wide variety of mailbox models. Always check the manufacturer instructions that came with your mailbox for more specific directions.


If Installing Post-Mounting Mailbox

If Installing Wall-Mounting Mailbox

How to Install a Post-mounted mailbox

post mailbox
dig post hole

USPS requirements state that a mailbox can be no taller than 45 inches above street level. Since most streets have a curb, the standard mailbox height is 42 inches above ground level. So the total height is around 45 inches: 42 inches from the ground, plus the few inches added by the curb.

• Measure the height of your mailbox post. USPS requirements state that a mailbox height must be 41 to 45 inches above the road's surface. Standard mailbox height above the ground is 42 inches. 
• Mark a spot on your lawn six to eight inches back from your curb. If you do not have a raised curb, contact your local postmaster for guidance.
• Use a post hole digger to dig a hole for your post at this spot. Dig deep enough that the height of your mailbox above the ground is around 42 inches. Do not dig deeper than 24 inches.

insert mailbox post

Make sure your desired mailbox post meets Federal Highway administration recommendations: a stable post that can bend or fall to the side if hit by a car. Avoid unyielding supports such as metal or concrete posts, and instead use a 4 x 4-inch wooden support or a 2-inch diameter standard steel or aluminum pipe.

• Insert the mailbox post into the hole. 
• Prop the post up with support beams on all sides, extending around the outside of the hole. Make sure these are secure and will not shift as the concrete is poured. 
• Measure the height of the mailbox above the ground to ensure it’s around 42 inches. 
• Do not bury your post deeper than 24 inches.
• Use a level to ensure the mailbox post is straight.
• If your chosen mailbox post comes with manufacturer's instructions, double-check that you are following those closely while you work through this guide's steps.

pour the concrete

• Prepare a bag of concrete per manufacturer’s instructions and pour into the hole, around the post. 
• Allow a few inches of space at the top of the hole – do not fill the concrete flush with the ground’s surface. 
• Immediately after pouring, use a level to double-check your mailbox. If it has shifted slightly uneven, adjust now before the concrete begins to dry. 

Tip: A 50-pound bag of concrete should suffice for this project.

allow concrete to set

• Allow the concrete to dry. The length of time this will take depends upon the type of concrete you used – check the concrete label for specifics. 
• Leave the support beams around the mailbox until you are certain the concrete is completely set.

attach the mailbox per manufacturer's instructions

• Attach mailbox using mounting brackets, per the installation instructions included with your unit. Each mailbox is different, depending on your model, so follow the instructions closely.
• Use the level to double-check the inside of your mailbox is flat.

Add street numbers

• USPS requires that each mailbox be clearly labeled with its corresponding house or apartment number.
• Add your street address or house number on the side of the mailbox with numbers at least one inch tall. 
• Per USPS guidelines, if your mailbox is on a different street than your home, put your full street address on the mailbox.

Tip: If you are constructing your own mailbox, contact your local postmaster to go over the mailbox plans and confirm the design follows USPS standards.

dress it up

• If desired, fill the few inches of hole above the concrete with soil.
• Improve your curb appeal by turning your mailbox area into a small garden in your front yard. See this Garden Club article for inspiration.
• Regularly inspect your mailbox to ensure it's holding up well against the weather and normal wear and tear. Once a year, check for loose hinges and rust. If you notice something has obstructed a clear path to the mailbox or that the house numbers have become lost or faded, fix the problem immediately.


wall-mounted mailbox
Mark the wall

• Hold the mailbox against the wall at it's desired installation location. 
• Double-check that this location is easily accessible from your sidewalk, front steps or porch so that the mail deliverer will not have any trouble finding it.
• Use a level to ensure you're holding the mailbox flat.
• Open the mailbox and insert a pencil through the mounting holes on the back of the mailbox to mark the wall.

Tip: Some wall-mount mailboxes come with an installation template that allow you to affix a sheet of paper or cardboard to the wall for easier marking.

drill holes

• Drill into the wall at each of the points you just marked. 

Tip: You don’t need to drill very deep for this installation. Typically, you can use a ¼-inch drill bit for brick or masonry walls and a 1/16-inch drill bit for wood walls. Check the installation instructions that came with your mailbox to double-check the requirements for your individual unit.

Install mounting hardware

• For masonry or brick walls, insert plastic anchors into each drilled hole and tap lightly if necessary. 
• Attach any hardware necessary to your mailbox or the wall as instructed on your mailbox’s installation manual. 

Tip: Often times, installation hardware is NOT included with your wall-mounted mailbox. Check the mailbox’s manual for specifics on what you need to purchase additionally for proper installation.

hang the mailbox

• Insert screws into the top holes and hang on the wall, only twisting the screws in halfway. 
• Rest a level on top of the mailbox to double-check it is flat. Adjust if necessary. 
• Insert screws into the bottom holes and drill in only halfway, again checking that mailbox is level.
 • Once you’re certain the mailbox is level, drill all screws in securely.