How to Install a Mailbox

Please, Mr. Postman, Is Mine Up to Code?

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In an era of email and text, regular snail mail often gets overlooked—as does the mailbox where it’s deposited.

But no matter how tied you are to Gmail, Snapchat, or Slack, you still need this classic receptacle (how else are you going to get those occasional postcards or Ikea catalogs?). And it needs to look good, be securely built and installed, and be fully up to code.

Apparently you can’t just plunk down whatever wherever you want. According to Sue Brennan, a spokesperson for the United States Postal Service, there are guidelines mandated by the USPS that must be followed so your neighborhood letter carrier can easily do the drop. Flout these rules, and you could get a gentle scolding from your mailman, or, if the mailbox is unusable, you might not receive your mail at all. Yikes! So play by the rules and learn how to install a mailbox right.

Step 1: Determine the right size and shape.  Mailboxes can’t be any old size; it must fall within the official range. The length should be approximately 18 9/16 to 22 13/16 inches; the width, 6 1/4 to 11 inches; and the height, 6 to 15 inches.

In terms of shape, you have some leeway. Dogs, fish, birds, miniature Chris Christie replicas—there are some cray-cray mailboxes out there. So go ahead and have fun; anything to make getting mail a bit more exciting sure can’t hurt.

Step 2: Pick the right mailbox post. Wood, lightweight steel, and aluminum are the correct materials for your mailbox post. Anything harder, such as concrete or thick steel pipe, won’t yield or bend if it’s accidentally struck by a car (or the mail truck). A wooden support should be 4 inches by 4 inches, while steel or aluminum piping must be 2 inches in diameter. Sink your post into the ground at a depth of no more than 2 feet.

Step 3: Figure out the best place to put the mailbox. When you’re ready to pound that post in, mark the distance carefully from your yard to the road’s edge. The mailbox should sit on the post 6 to 8 inches away from the curb (if your street doesn’t have a curb, contact your local post office for placement assistance). The box’s height should be between 41 and 45 inches from its bottom to the road’s surface. Put your home’s address on the box, too.

Step 4. Make sure the mail slot is the right size—wherever it is. No box? No problem! A slot on your front door will do just fine as long as the opening is 1.5 inches wide and 7 inches long and the bottom of the slot is at least 30 inches from the floor. If your slot is horizontal, the flap must be hinged at the top; vertical slots should have the hinge on the opposite side from the door’s hinges.

Step 5. Maintain your mailbox! “Make sure the mailbox’s door is working well,” Brennan advises. Tighten hinges, remove rust, and repaint (or replace) faded house numbers on the outside. You’ll also need to keep the path to the post clear, so trim plants and shrubs and be sure they don’t interfere with the opening and closing of the box. And once you’ve retrieved your mail, close the box up tight so nothing else can get in and occupy the space.

“We’ve seen it all—snakes, large spiders, and beehives,” she adds. Now, who said getting mail isn’t exciting?