Mailbox Install

Mailboxes and Newspaper Delivery Boxes Along County Roads

Most rural mailboxes are located immediately adjacent to the road to allow for efficient delivery of mail. Placement adjacent to a road, however, can be a hazard to the motoring public. Accordingly, the Washtenaw County Road Commission has adopted standards for the placement of mailboxes and newspaper delivery boxes along county roads. These standards conform to the rules and regulations of the U.S. Postal Service and are based on "A Guide for Erecting Mailboxes on Highways" published by the American Association of State Highway & Transportation Officials 1994.

No mailbox or newspaper delivery box (hereafter referred to as mailbox) will be allowed to exist within the County's rights-of-way if it interferes with the traveling public or the function, maintenance, or operation of the county roadway system. A mailbox installation that does not conform to the provisions of this regulation is prohibited.


The roadside face of the box shall be offset the following distances:

  • Paved road - the width of the shoulder plus one foot.
  • Gravel road - one foot from the edge of the traveled portion of the roadway.
  • Curbed street - one foot from the face of the curb.

Where a mailbox is located at an intersecting road it shall be placed a minimum of 100 feet beyond the center of the intersecting road in the direction of the delivery route. This distance should be increased to 200 feet when the average daily traffic on the intersecting road exceeds 400 vehicles per day.

Where a mailbox is installed in the vicinity of an existing guardrail, whenever practical, it shall be placed behind the guardrail.


Mailboxes shall be constructed from sheet metal, plastic, or similar weight materials and shall not exceed 11 lbs.

No more than two mailboxes shall be mounted on a support structure unless the support structure and mailbox arrangement have been shown to be safe by crash testing, approved by the U. S. Department of Transportation. Newspaper boxes may be mounted below the mailbox on the side of the mailbox support.

Multiple mailbox installations must meet the same criteria as do single mailbox installations. This requirement precludes the use of a heavy horizontal support member. It is recommended that mailbox supports be separated a distance at least equal to three-fourths of their heights and preferably their full heights above ground. It is also preferred that multiple mailbox installations be located outside the highway clear zone, if feasible, such as on a service road or minor intersecting road.

A single 4 inch by 4 inch square or 4 inch diameter wooden post, or a metal post with a strength no greater than a 2 inch diameter standard steel pipe and embedded no more than 24 inches into the ground will be acceptable as a mailbox support. A metal post shall not be fitted with an anchor plate, but may have an anti-twist device that extends no more than 10 inches below the ground surface. Larger wooden posts may be used provided the posts have drilled holes and the support design has been shown to be safe by crash testing, approved by the U. S. Department of Transportation.

The post-to-box attachment details should be of sufficient strength to prevent the box from separating from the post top if the installation is struck by a vehicle.

Exceptions to the above listed supports shall not be used unless previously approved in writing by the Washtenaw County Road Commission

Removal of Non-Conforming or Unsafe Mailboxes

Any mailbox that is in violation of these regulations shall be immediately removed by the owner upon notification by the Road Commission. If the owner has not removed the mailbox, the owner will be issued an Encroachment Removal Order by the Road Commission in accordance with M. S. A. 9.251, whereupon the owner will be granted 30 (thirty) days to remove the unacceptable mailbox. Thereafter, the mailbox will be removed by the Road Commission at the owner's expense.