Port Townsend, WA Accessory Structures: ADU Rental Restrictions (2026)
Key Facts
- Max ADUs per lot
- 2
- ADU size cap
- 1,000 sq ft
- Short-term rental of ADU
- Prohibited
- Exception
- Main house as tourist home only
- Civil penalty
- $250 per day
Summary
Port Townsend prohibits both the main house and any accessory dwelling unit from operating as a short-term rental once an ADU is established on the property, per PTMC 17.16.020(C)(2).
C. Accessory Dwelling Units – Limitations on Use. Two accessory dwelling units (ADU) may be established as an accessory use to a single-family detached, shotgun house, duplex, triplex, or townhome residence provided the following conditions are continuously met:
1. A certificate of occupancy pursuant to the currently adopted city construction codes shall be obtained from the building official and posted within the ADU. The code inspection and compliance required to obtain a certificate of occupancy in an existing building shall be restricted to the portion of the building to be occupied by an ADU and shall apply only to new construction rather than existing components, except that any high hazards (i.e., smoke detectors, fire exits, stairways, LP gas appliances and fire separation) shall be corrected. Where additional fire separation is unduly burdensome, the building official may authorize a fire alarm system in lieu of required fire separation.
2. Neither the main nor accessory dwelling units shall be used as a short term rental, except as provided for in PTMC 17.57.020(B)(2).
3. ADUs established in an outbuilding shall not exceed 1,000 square feet in floor area and ADUs established within or attached to the primary residence shall not exceed 1,000 square feet, and under no circumstance shall the total lot coverage of the primary residence along with the ADU exceed the standard allowed in the underlying zoning district.
Official source re-checked September 8, 2026: no newer edition of the code had been published (publisher’s edition: current through Ordinance 3364, passed May 18, 2026).
Full Breakdown
Under PTMC 17.16.020(C), an owner may add up to two accessory dwelling units to a single-family detached, shotgun house, duplex, triplex, or townhome residence, but keeping that approval requires that neither the main house nor the ADU be used as a short term rental. The only carve-out is PTMC 17.57.020(B)(2), which lets the primary residence operate as a licensed tourist home even with an ADU on the same lot: the ADU itself still cannot host short-term guests. ADUs are capped at 1,000 square feet and need a certificate of occupancy from the building official.
Violations & Fines
Renting the main house or ADU short-term outside the tourist-home carve-out breaks the certificate-of-occupancy conditions; the city can issue a notice and order under PTMC 1.20.075 carrying a $250-per-day civil penalty plus cost recovery.
Frequently Asked Questions
Can I list my Port Townsend ADU on Airbnb?
Is there any short-term rental workaround with an ADU on site?
Sources & Official References
Other rules in Port Townsend
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