Don't Mail It In: Here's How to Install a Mailbox

by Team eLocal
A gray mailbox sits with its red flag up and door open atop a brown wooden post against the backdrop of a cloudless blue sky

Your mailbox might be filled with bills and junk mail, but you still need one installed and ready for the more fun pieces of mail, like packages and wedding invitations.

Installing a mailbox is relatively easy. The main concern is following the regulations, so you don't face the wrath of your mail carrier.

U.S. Postal Service Mailbox Regulations

Even though your mailbox is on your property, you need to follow the rules established by the U.S. Postal Service. The regulations can vary by area and based on how your mail gets delivered. Some mail carriers deliver mail to boxes installed by the road, while others walk up to homes and put the mail in boxes mounted to the side of the building. Before you make any changes to your mailbox or install a new one, contact the postmaster and your local post office to get the changes or installation approved.

Check with your post office for specific regulations pertaining to your home. In general, these regulations apply:

  • Post-mounted mailboxes should sit so the bottom is 41 to 45 inches above the road.
  • They should be positioned in a place where the mail carrier has a clear approach without obstructions.
  • Mailboxes should sit 6 to 8 inches back from the curb.
  • Your house or apartment number should be placed on the mailbox in letters or numbers that are at least 1 inch tall.
  • The slot needs to be large enough to accommodate a normal amount of mail if the box is locked.
  • USPS-approved mailboxes are the only type you should use; custom-made mailboxes need to be approved by the postmaster.

How Do You Install a Mailbox?

A wall-mounted mailbox on the side of your house is generally the easiest to install because you simply need to screw it down. A post-mounted mailbox takes more work, especially if you don't already have a post installed.

Installing a Wall-Mounted Mailbox

1. Choose the location. It should be near your front door and easily visible to your mail carrier.

2. Hold the mailbox where you want it and use a level to ensure the mailbox is flat and appropriately positioned.

3. Use a pencil or marker to mark the mounting position. Your wall-mounted mailbox should have mounting holes along the back. Make the marks in the center of those holes. Your mailbox might also include an installation template that helps.

4. Drill starter holes for the mailbox. You might need special tools based on your siding type. For example, a brick wall typically requires a masonry bit for your drill.

5. Install the anchors or other mounting hardware per the instructions of your mailbox.

6. Position the mailbox over the mounting hardware. Insert the screws through the mounting holes and secure them just until they're tight.

7. Check the positioning and make adjustments if necessary.

Installing a Post-Mounted Mailbox

For a post-mounted mailbox, you'll need a securely installed wood or metal support. A 4-inch by 4-inch wood post, or a steel or aluminum pipe that's 2 inches in diameter is ideal. You don’t want it to be too much thicker than that; for safety reasons, the post has to be able to bend or break if a car hits it.

You can also buy mailbox posts that have mounting platforms attached to them. If you already have a sturdy post installed at the proper location, you can skip ahead to the mounting step.

1. Mark the location for the hole. Remember that the mailbox should be between 6 and 8 inches back from the curb. Your postmaster can give you guidance on what to do if your street doesn't have a raised curb.

2. Dig a hole that's no deeper than 24 inches.

3. Position the post in the hole, using support beams to hold it in place. Check the top of the post to ensure the bottom of the mailbox will fall between 41 and 45 inches above the road, not above the ground. Verify that it's straight by using a level.

4. Mix and pour fast-setting concrete around the post in the hole to secure the post, leaving a few inches between the top of the concrete and the ground, so you don't completely fill the hole. This allows you to cover the concrete with soil once it cures.

5. Check that the post is still level before the concrete dries. Make adjustments if necessary.

6. Wait for the concrete to dry based on the package instructions.

7. Attach the mailbox to the post using the mounting brackets that come with it. Follow the instructions with your mailbox since the mounting styles can vary. You can also buy separate mounting brackets for a 4-inch by 4-inch post if your mailbox doesn't include them.

8. Verify that the mailbox is level and at the appropriate height according to the regulations.

9. Apply your street address to the sides of the mailbox.

Once the mailbox is installed, you can plant flowers around it or otherwise dress it up. Just ensure your decorations don't interfere with the mail carrier's ability to reach the mailbox or read the address on the side.