The Mounting Height for a US Residential Mailbox

Height of Post

• Mailboxes should sit on a post that is between 41 and 45 inches tall if it is a roadside unit and 6 to 8 inches from the end of the curb. This will conform to the height of mail trucks that postal workers drive, allowing them not to have to leave their vehicles when delivering your mail. Given the different curb and roadway heights, check with your local postmaster for the exact height they want roadside mailboxes to be.

Wall Attached

• A mailbox attached to an outside wall or a porch post should be about 4 feet off the ground. This will allow the postman, who carries a heavy mail bag, an easy reach into the mailbox. When placing your mailbox, keep in mind the path and reach of the postman.

Door Slots

• Slots on doors for mail should be at least 30 inches from the ground. This will allow the mail carrier to easily reach and drop in the mail instead of having to bend or stretch to insert mail into the slot. The opening should be between 1.5-by-7-inches.

The Post

• Guidelines set forth by the Federal Highway Administration say the a wooden mailbox support should be no bigger than 4 inches-by-4 inches while a standard steel or aluminum pipe support should be 2 inches in diameter. The post should be dug 2 feet into the ground. These guidelines ensure the post will give if a vehicle hits it.