Marysville, WA Short-Term Rentals: Occupancy Limits (2026)

Marysville's zoning code (Title 22) does not define a stand-alone short-term rental use with its own occupancy formula. Maximum overnight occupancy in any dwelling, including a unit listed on Airbnb or Vrbo, defaults to the Washington State Building Code (Chapter 19.27 RCW), which adopts the International Residential Code (IRC) and is applied locally through MMC Title 16. IRC Section R304 requires every habitable room to have a minimum floor area of 70 square feet, and IRC R304.2 sets a per-occupant minimum of 50 square feet for any room used for sleeping by more than one person. The State Building Code sets a hard limit of one family plus two unrelated boarders for a single-family dwelling under the Residential Code definition of family, although Marysville's zoning definitions in MMC 22A.020 may apply a broader "family" definition. Bed and breakfast guesthouses are separately regulated under MMC Chapter 22C.210, which typically limits B&Bs in residential zones to a small fixed number of guest rooms. STR operators should confirm both the building-code sleeping room calculation and any guest-room cap with Marysville Community Development at 360-363-8100 before listing. Washington's STR Operations Act in RCW 64.37 requires all operators to register with the Department of Revenue and maintain $1 million in liability coverage (or rely on platform-provided coverage), but it does not preempt local occupancy limits.