How to Install a Mailbox Post

Man mailing letters in a mailbox
  • 2-5 hours
  • Intermediate
  • 0-350
What You'll Need
Mailbox post
Post hole digger
Concrete Mix
Tape measure

Installing a mailbox post is actually a trickier job than most people think. There are several very important things that must either be done or at least taken into consideration before you simply dig a hole and shove a post in. Below are some basic steps to help you with the installation of your new residential mailbox.

Step 1 - Talk To The Authorities

There are regulations regarding the placement of a US mailbox that must be adhered to, though nothing specific as far as height or distance from the curb. According to regulations put in place in 2004, your mailbox has to be approved by the post office and set to such a distance and height that the postal carrier does not have to leave their vehicle. As a guideline for placing your mailbox, many people use the standards the post office had prior to 2004; a vertical height from the road to your mailbox had to be between 41 and 45 inches, with the outside edge of the curb or road to the mailbox between six and eight inches.

You should go over your specific plans for your mailbox with a clerk from the post office to ensure your new mailbox will be considered deliverable.

Also, check with city and/or county records to ensure that there are no power lines, gas lines, etc. running underneath the spot you plan to put your mailbox.

Step 2 - Prepare Your Hole

Use your post hold digger to dig the hole roughly two feet down, or as deep as recommended for your specific mailbox post. Dig an extra four or five inches, and fill the extra space with sand or gravel; this will allow water drainage and help prevent water damage over the years. This should be done for ANY wooden post, even such wood as Cedar, which is reputedly resistant to such damage.

Step 3 - Concrete

cementing in a mailbox post

Use your wheelbarrow to get your concrete mixture ready, following the instructions on the concrete’s bag.

Step 4 - Place Your Post

Place your post in the hole, using a level to keep it plumb. Pour or shovel the concrete in small amounts at a time, and continue to re-check the post to ensure that it stays level. If you like, you may fill the concrete all the way to the surface, but this tends to be unsightly. It is better to leave the top of the concrete about five or six inches from surface level; this will be plenty to hold your mailbox in place.

Give your concrete at least 24 hours to dry, or however long specified in the instructions. Once dry, if it was left below surface level, fill in the rest of the hole with dirt and tamp it down.

Step 5 - The Mailbox

Go ahead and attach the mailbox of your choice. Double check with your tape measure to be sure that it sits at roughly the correct position for the mailman.