King County, WA Home Business: Zoning & Home Occupation Permits (2026)
Key Facts
- Floor area cap (R/UR/NB/CB/RB)
- 20% of dwelling unit
- On-site nonresident employees (R/UR/NB/CB/RB)
- 1 maximum
- On-site nonresident employees (A/F/RA)
- 3 maximum
- Customer hours
- 8am-7pm weekdays, 9am-5pm weekends
- Barred uses
- auto repair, towing, vet clinics, cannabis
Summary
Unincorporated King County caps home businesses at 20% of a dwelling's floor area and one on-site nonresident employee in residential and commercial zones.
In the R, UR, NB, CB, and RB zones, residents of a dwelling unit may conduct one or more home occupations as accessory activities, as follows: A. The total floor area of the dwelling unit devoted to all home occupations shall not exceed twenty percent of the floor area of the dwelling unit... No more than one nonresident employee shall be allowed to work on-site for the home occupation or occupations.
Full Breakdown
In unincorporated King County's R, UR, NB, CB, and RB zones, home occupations run by dwelling-unit residents can't use more than 20% of the unit's floor area, must operate indoors (except growing/storing plants), and are capped at one nonresident employee working on-site. Rural A, F, and RA zone home occupations get outdoor storage allowances by lot size instead. Auto repair, towing, dry cleaning, veterinary clinics, and cannabis businesses are barred outright as home occupations under K.C.C. 21A.30.080 and 21A.30.085. This is unincorporated county code only. Seattle, Bellevue, Kent, Renton, and other King County cities enforce their own separate home-occupation rules.
Violations & Fines
Code enforcement (Department of Local Services, Permitting Division) issues notices to correct; exceeding the floor-area, employee, or use limits can trigger civil penalties and, on continued noncompliance, code enforcement action under K.C.C. Title 23.
Frequently Asked Questions
Can I run a home business from my house in unincorporated King County?
Does this apply inside Seattle or Bellevue?
Sources & Official References
Other rules in King County
How King County compares: Easiest Cities to Run a Home Business·Compare King County to another location·View the Washington home business overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.