The responsibility to maintain a boundary fence falls on the owners of the property who use the fence, according to FindLaw. Each state and municipality has its own rules and regulations to define the term "use."
Use is defined in one of three ways, explains FindLaw. Occupancy is the use of the land that backs up to the fence. The term "join" involves attaching another fence to the boundary fence. An entire enclosure occurs when joining a fence to the boundary fence encloses an entire piece of property.
When a boundary fence needs repairs, it is the responsibility of both property owners. If one owner refuses to pay for repairs, the other property owner can take him to court to enforce payment.