What Is the Good Neighbor Fence Law in Idaho?

The good neighbor fence law in Idaho, set out in Title 35, Chapter 1 of the Idaho Code, requires adjoining landowners to share the cost of building and maintaining a boundary fence that meets the state’s specifications. If you need a partition fence to protect your property, your neighbor is obligated to build and pay for half of it. If they refuse, you can build the whole thing, sue for their share, and hold a lien on their land until they pay.¹

That’s the short version. The details decide whether you actually collect.

What Counts as a Lawful Fence

None of the cost-sharing rules apply unless the fence meets Idaho’s minimum standards. Under Idaho Code 35-101, a lawful fence stands at least four and a half feet high, with the bottom board, rail, pole, or wire no more than 20 inches off the ground and the space between top and bottom evenly divided.²

Idaho Code 35-102 adds material-specific rules:

Stone fences: at least four feet high, with a two-foot base and one foot thick at the top.
Worm (zigzag rail) fences: well laid and at least four feet high.
Post-and-board, rail, or pole fences: posts set firmly no more than eight feet apart, with at least three boards or rails, top rail at least four feet off the ground, spacing evenly divided, everything securely fastened.
Wire fences: posts no more than 24 feet apart (16 feet for barbed wire only), three substantial stays between posts, at least three barbed wires or four coiled spring wires of number-nine gauge or heavier, and a height of at least 47 inches. Woven wire works too if it meets the gauge and spacing requirements.

Natural barriers such as creeks, rivers, bluffs, and mountains count as lawful fences if they present a suitable obstruction to livestock.²

How to Make a Neighbor Pay Their Half

Idaho Code 35-103 governs partition fences. When two or more people own adjoining enclosed land and one of them needs a boundary fence to protect their interests, the neighbor must build half. The fence goes on, or as close as practical to, the property line.¹

The process begins with written notice. Once you serve it, each side has six months to build its half. If your neighbor doesn’t build in that window, you can construct the whole fence yourself, then recover half the cost through legal action. The statute also gives you a lien on your neighbor’s land until they pay.¹ The lien is the real enforcement tool, and most landowners don’t learn it exists until they need it.

Who Maintains Which Side

Once the fence is up, Idaho Code 35-104 sets the maintenance split. Unless both owners agree otherwise, each is responsible for the half of the boundary fence that falls to their left when they stand on their own land facing the neighbor’s property.³ Face your neighbor, keep the left.

There’s one wrinkle worth remembering. If you upgrade your side of the fence for your own convenience, say by adding wire to make it hog-tight, your neighbor owes nothing for the improvement. But the moment they start pasturing hogs, sheep, or goats and rely on that upgrade to contain them, they become a joint user and must pay their proportional share on demand.³

When Your Neighbor’s Land Was Previously Unenclosed

Sometimes you’ve already fenced your side of the line and your neighbor’s land has sat open for years. If they later enclose their property using your existing fence as one of its boundaries, Idaho Code 35-105 requires them to pay you half the fence’s value. From then on, both of you split ongoing maintenance equally.⁴ No one gets to freeload off a fence their neighbor paid for in full.

When You and Your Neighbor Disagree: Fence Viewers

Idaho doesn’t send every fence fight straight to a lawsuit. Under Idaho Code 35-106, if adjoining owners can’t agree on how to divide building responsibilities, how much an existing fence is worth, or who maintains which section, either party can ask a magistrate judge to appoint three fence viewers.⁵

You have to give the other side five days’ notice. The viewers can take sworn testimony, inspect the property, and issue a written determination covering two things: how much an existing fence is worth and what share the other owner owes, and which portion of any unbuilt fence each party must construct and maintain. Their written determination is filed with the county recorder and binds both sides.⁵

If a viewer finds that one party owes the other for the fence, payment is due within 30 days. Nonpayment is recoverable in court.

Taking a Shared Fence Down

You can’t just rip out a partition fence. Idaho Code 35-111 lets you remove your share if you’re vacating your enclosure or opening a lane between properties, but only after giving the adjoining owner six months’ written notice. If the neighbor lives out of county, notice goes to their agent.⁶

Idaho Code 35-107 adds a crop-protection restriction. Even your own portion of a partition fence can’t come down if removing it would expose crops in the adjoining enclosure to destruction. The neighbor can keep the fence standing by paying its agreed value, or by using the fence viewer process if the two of you can’t settle on a price.

Making Sure the Fence Is Actually on the Line

If anyone questions whether the fence sits on the true boundary, Idaho Code 35-110 lets either the builder or the landowner hire a licensed surveyor to establish the line. Whoever built the fence in the wrong place has one year after the survey to move it.⁷ You must notify the other party before the survey. And under Idaho Code 35-108, anyone who built a fence on another person’s land by mistake has one year from discovering the error to remove it.

Paying a surveyor before you build is far cheaper than moving a completed fence later.

Open Range vs. Herd District

Idaho is an open-range state, and that single fact can flip who bears the fencing burden. Idaho Code 25-2118 defines open range as all unenclosed land outside cities, villages, and herd districts where cattle graze or are allowed to roam by custom, license, lease, or permit. In open range, the duty to fence falls on the landowner who wants to keep livestock out, not on the owner of the livestock. If your neighbor’s cattle wander onto your unfenced property in open range, that’s generally your problem.⁸

Livestock owners on open range also have no duty to keep animals off highways and no liability for vehicle collisions involving their animals on open-range roads.⁸

Herd districts flip that default. Under Idaho Code 25-2401, county commissioners can create, change, or dissolve herd districts within their counties. Inside a herd district, livestock owners must keep their animals contained, and the open-range protections fall away.⁹ Since January 1, 1990, counties can regulate livestock running at large in unincorporated areas only through the herd district process.

Before you build, call your county and ask whether your property sits inside a herd district. The answer changes who is responsible for keeping livestock on which side of the line.

City Rules, HOAs, and Calling 811

The state statutes set a floor. City and county ordinances often add their own ceilings. Municipal zoning codes commonly cap residential fence heights (often around six feet in side and rear yards and three feet in front yards) and may require permits before construction. Rules vary by jurisdiction. In the City of Eagle, any residential fence in a front yard or along a street requires a fence permit regardless of height, and fences over six feet tall need an additional building permit.¹⁰ Your city or county planning department can tell you what applies to your lot.

If your property is governed by CC&Rs, your HOA may restrict materials, colors, and heights beyond what municipal code requires. HOA restrictions are contractual rather than statutory, but they are enforceable, and violations can bring fines or a demand to tear the fence down.

One last step people skip: call 811 before you dig post holes. The national “Call Before You Dig” line sends utility companies out to mark underground gas, electric, and water lines at no charge, and the law requires contacting them at least two to three working days before any excavation. The marks cover public utility lines up to your meter; anything on the private side may need a separate private locator. A fence post through a gas line or fiber-optic cable turns a weekend project into an emergency.

1
Idaho State Legislature. Idaho Code 35-103 – Erection of Partition Fences
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Idaho State Legislature. Idaho Code 35-101 – Lawful Fences in General
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Idaho State Legislature. Idaho Code 35-104 – Care of Fences by Adjoining Owners
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Idaho State Legislature. Idaho Code 35-105 – Use of Division Fence in Making Inclosure
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Idaho State Legislature. Idaho Code 35-106 – Disagreement Between Owners, Viewers
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Idaho State Legislature. Idaho Code 35-111 – Removal of Partition Fences
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Idaho State Legislature. Idaho Code 35-110 – Survey of Line
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Idaho State Legislature. Idaho Code 25-2118 – Animals on Open Range
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Idaho State Legislature. Idaho Code 25-2401 – Commissioners May Create Herd Districts
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City of Eagle. Fences and Retaining Walls