Yes, there are. USPS guidelines state that post mount mailboxes should be installed at a height of 41-45 inches from the road surface to the bottom of the mailbox, and face 6-8 inches away from the road. With this height and setback, the postal driver can pull up to your mailbox, deliver your mail and drive away; all from the seat of the vehicle. Were the box to be set too low, or too far off the curb it would be difficult to reach.
Once set, the mailbox or post should have a reflector so that it is clearly visible to oncoming traffic at night. This will reduce the chances of it getting hit. Last, the mailbox should clearly display the address (numbers) for your home. If your mailbox is on a different street than your home, put your full street address on the box.
Some homes have a slot in the door for receiving mail instead of a mailbox. The standards for an approved door slot are: the opening must be at least 1 1/2″ x 7″; the bottom of the slot must be at least 30″ above the street; horizontal slots must have a flap hinged at the top and, vertical slots must be hinged on the opposite side from the door's hinges.
