Fence Regulations in Washington County, OR (2026)
4 county-level rules, plus city-specific rules for 2 cities in Washington County, Oregon.
Verified from official government sources
Height Limits
Fences in unincorporated Washington County top out at 7 feet in any required yard under Section 419-3, rising to 8 feet where the yard abuts an arterial or limited-access highway. A separate corner-vision rule caps sight-obstructing fences at 3 feet within 20 feet of a street corner.
Washington County Fence Height Limit: 7 Feet
Some RestrictionsWashington County Community Development Code § 419-3
419-3A fence, lattice work, screen or wall (includes retaining wall) not more than 7 feet in height may be located in any required side, front or rear yard, except as required by Section 418-3 (corner vision). Where a rear, side or front yard abuts an arterial or limited access highway, fence height along the yard may be increased to 8 feet.
Fence Permit Requirements
A building permit is required in unincorporated Washington County for any fence over 7 feet tall, and for any retaining wall over 4 feet, under Section 419-3. Fences and retaining walls at or below those heights can go up without a building permit, though other yard and setback rules still apply.
Washington County Fence Permit Threshold: 7 Feet
Some RestrictionsWashington County Community Development Code § 419-3
Any fence over 7 feet in height requires a building permit. Any retaining wall over 4 feet in height requires a building permit (the height measurement of a retaining wall is from the bottom of footing to the top of the retaining wall).
Retaining Walls
Standalone retaining walls in unincorporated Washington County are capped at 7 feet under Section 419-5, while a combination fence-and-retaining-wall structure follows a different formula: a 4-foot wall topped by a 6-foot fence, for a 10-foot combined lowest-side measurement, under Section 419-4.
Washington County Retaining Wall Height Rules
Some RestrictionsWashington County Community Development Code §§ 419-4, 419-5
419-4A combination fence and retaining wall structure may be located in a side or rear yard. This structure shall consist of a retaining wall [not more than 4 feet in height] and a fence [not more than 6 feet in height]. ... The non-back-filled or lowest side measurement may not exceed a combined total of 10 feet in height. ... 419-5Tiered retaining wall structures shall not exceed 7 feet in he...
Material Restrictions
Inside mapped Riparian Wildlife Habitat within the urban growth boundary, Washington County allows new fencing only if it lets wildlife pass through: a split-rail-style design with the lowest rail 18 inches off the ground, the top rail no higher than 42 inches, and no woven wire, cyclone fencing or barbed wire.
Washington County Riparian Fence Material Rule
Some RestrictionsWashington County Community Development Code § 422-8.2(G)
G. Fencing provided it is split rail or other design that allows for the passage of wildlife by meeting the following design requirements: 1. The lowest horizontal fence element must be at least 18 inches off the ground. 2. The highest horizontal fence element must be no more than 42 inches in height. 3. Fencing shall not include woven wire, cyclone fencing, or contain barbed wire elements.
Fence Regulations by City in Washington County
2 cities in Washington County have their own fence regulations rules. Each link goes to that city's dedicated page with code citations.
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