Snohomish County, WA Accessory Structures: Tiny Homes (2026)
Tiny home rules in Snohomish County, WA, covering tiny houses on wheels (THOWs), park model RVs, and tiny home on foundation builds, determine where they are legal and how they get permitted.
Key Facts
- RV as primary home
- Not allowed
- RV definition
- SCC 30.91R.050
- Temporary RV parking
- 180 days per 12 months
- Permanent tiny home
- Foundation + permit + utilities
- Legal path
- Dwelling/ADU under Title 30
Summary
In unincorporated Snohomish County a recreational vehicle cannot be a primary residence. A tiny house counts as a dwelling only if built on a foundation, permitted, and connected to water and sewer; a tiny house on wheels is regulated as an RV.
"Recreational vehicle (RV)" means a travel trailer, motor home, truck camper, or camping trailer that is permanently designed and used as temporary living quarters, is either self-propelled or mounted on or drawn by another vehicle, is transient, and is not immobilized or permanently affixed to a mobile home lot. (Added by Amended Ord. 02-064, Dec. 9, 2002, Eff date Feb. 1, 2003).
30.91R.060 Recreational vehicle (RV) park. "Recreational vehicle (RV) park" means land under single ownership or control designed and improved to accommodate the temporary parking of two or more recreational vehicles. The term shall include campgrounds when designed to accommodate recreational vehicles, but does not include land zoned and used for the storage, display or sale of recreational vehicles. For the purposes of this definition, temporary parking shall mean placement of a recreational vehicle on a single site for 180 days or less in any 12-month period. (Added by Amended Ord. 02-064, Dec. 9, 2002, Eff date Feb. 1, 2003).
30.91R.065 Recycling facility. "Recycling facility" means any facility which transforms or remanufactures waste materials into usable or marketable materials for use other than disposal or incineration. Recycling facilities do not include facilities which collect, compact, repackage, and sort for the purpose of transport. (Added by Amended Ord. 16-013, Mar. 8, 2017, Eff date May 7, 2017).
30.91R.070 Redevelopment.
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through legislation passed August 12, 2026).
Full Breakdown
SCC 30.91R.050 defines a recreational vehicle as a travel trailer, motor home, truck camper, or camping trailer permanently designed and used as temporary living quarters, transient, and not permanently affixed to a mobile-home lot. RVs may serve as temporary living quarters, but temporary parking means placement on a single site for 180 days or less in any 12-month period, and an RV cannot be a primary residence. A permanent tiny home must be sited as a dwelling or ADU on a foundation with a building permit and utility connections. Cottage-housing and ADU pathways under Title 30 are the routes to a legal permanent small home.
Violations & Fines
Living in an RV or unpermitted tiny structure as a permanent residence is a code violation; the county may order removal or connection to permitted utilities, with civil penalties.
Frequently Asked Questions
Can I live in an RV on my land year-round?
Are tiny homes allowed?
Sources & Official References
Other rules in Snohomish County
Compare Snohomish County to another location·View the Washington accessory structures overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.