Jefferson County, MO Fence Regulations: Neighbor Fence Rules (2026)

2860, Fence or Masonry Wall - Accessory Use, sets height and placement rules for all fences and masonry walls in residential zoning districts. In the front yard setback, a fence or wall is capped at 4 feet in the "R-40", "R-20", "R-10", and "R-7" districts. In the "RA-5" Rural/Agricultural and "LR-2" Large Lot Residential districts that cap rises to 8 feet, but only for material that is two-thirds open space to one-third closed space per square foot, such as picket or split rail fencing, for the portion of the fence above 4 feet.

On the rear property line, a fence or wall up to 8 feet tall is allowed on any lot whose rear line abuts another lot or a designated thoroughfare, but no fence may sit inside a required landscape area unless the County approves it. On the side property line, fences up to 8 feet are likewise allowed, except that on a corner lot no fence or wall over 4 feet may stand in front of the front setback line, protecting visibility at the corner; a side-yard fence may otherwise be built to match a front-yard fence permitted under the district's front-yard rule.

2860(B) permits a fence or wall on any side or rear property line, but bars it from a required front yard setback or from standing closer to a public or private street than the building setback requires, unless an approved development plan says otherwise.