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Colorado Fence and Trespass Law   arrow

Either living in an urban area or on the rural landscapes of Colorado the old adage “Good fences makes good neighbors” rings true still today.  In the early years of statehood, Colorado enacted the “Fence Law” or “Open Range Law” and this legislation is still in force today with some revision. The Fence Law in Colorado addresses key items like defining what a lawful fence is, who is responsible for construction and maintenance of lawful fence and who can claim damages for trespass.   This article is a summation of the Colorado Statutes that pertain to the “Fence Law”.

The Colorado Statutes #35-46-101 clearly defines two important terms for addressing issues that apply to fencing and trespass “Lawful Fence” and “Livestock”.  The following are the definition of the terms from the Colorado Revised Statutes and they should be referred to when building, maintaining, repairing and replacing any fences.

“Lawful fence” is a well-constructed three barbed wire fence with substantial posts set at a distance of approximately twenty feet apart, and sufficient to turn ordinary horses and cattle, with all gates equally as good as the fence, or any other fence of like efficiency.  “Livestock” includes horses, cattle, mules, asses, goats, sheep, swine, and buffalo. In working toward resolution in disputes of livestock grazing the first determination is if a “Lawful Fence” was in place and properly maintained.

Construction and Maintenance of “Lawful Fence”

In Colorado it is the responsibility of the landowner to fence out any livestock from their property with a “Lawful Fence”.  Colorado Statute #35-46-112 puts the burden of the cost of constructing or repairing a fence on adjoining properties on both land owners. Caution should be taken in that the statute only requires a land owner to meet the standard of the definition of a lawful fence. If one land owner wants to make the fence to a higher standard that landowner may be responsible for the additional costs.  In any case they should follow the procedure set forth in Statute #35-46-113 – If after thirty days written notice (certified letter), served personally or by registered mail by either owner or tenant of another, if such owner neglects or refuses to erect or repair one-half of the partition fence, the person giving notice then may undertake repairs and may collect by a civil action one-half of the cost.  Refers only to a “Lawful fence”.  It is always good practice to have written documentation of all agreements and how you complied with the above procedure before purchasing any materials.

Livestock Trespass

Colorado Fence Laws benefit the livestock owner by putting the responsibility on landowners and crop producers to fence out.  Livestock owners are not liable for animals that wonder on to property that a “Lawful Fence” is not maintained. Colorado Statute #35-46-102 does give provision that helps protect landowners from stock produces that knowingly drive herds on to another person’s land or from repeated livestock trespass where a “Lawful Fence” is in place and maintained to recover damages through a civil court process.  In any case of livestock trespass it is best that you keep local sheriff’s office and brand inspection office involved.

There are some generalizations that can be made in helping with issues that arise between neighbors in regards to livestock and fencing:

  • Always refer to updated Colorado Revised Statutes on Fencing Laws and consult with local law enforcement and brand inspection.
  • Make sure that a “Lawful Fence” is in place and that it is regularly maintained.
  • Colorado fence laws favor the livestock owner and put the duty of protecting property on the landowner.
  • An open and good working relationship with adjacent landowners is the best prevention for issues with livestock and fencing.

This article was prepared to help address perception and concerns that landowners have with Colorado Fencing Law. Information was taken from Colorado Revised Statutes and the Colorado Department of Agriculture. It is recommended that landowners should obtain a full updated copy of the statutes before taking any action in regards to fencing laws or contact your local CSU Extension Agent for additional information.


Colorado Revised Statute on Fencing Laws. CO Dept. of Agriculture Open Range and Fencing

Fencing with Wildlife in Mind. Colorado Division of Wildlife