ADU (Accessory Dwelling Unit) Permit in Tacoma (2026)
ADU (Accessory Dwelling Unit) permit requirements, fees, and process for Tacoma, WA. Find out if you need a permit and how to apply.
Yes, a ADU (Accessory Dwelling Unit) permit is required in Tacoma, WA.
A ADU (Accessory Dwelling Unit) permit is required in Tacoma, WA. The City of Tacoma Planning and Development Services — Building handles permit applications for Tacoma. Below you will find the current thresholds, fees, and process for obtaining a adu (accessory dwelling unit) permit in Tacoma.
When Is a Permit Required?
When a ADU (Accessory Dwelling Unit) Permit Is Required in Tacoma: All ADU construction
Permit Fees
ADU (Accessory Dwelling Unit) Permit Fees in Tacoma: $1,000–$5,000. Estimated timeline: 3-6 weeks.
Estimated timeline: 3-6 weeks
How to Get a ADU (Accessory Dwelling Unit) Permit in Tacoma
Verify whether your project meets the permit threshold in Tacoma: All ADU construction.
Prepare your permit application and plans. Contact the City of Tacoma Planning and Development Services — Building at https://www.cityoftacoma.org/government/city_departments/planning_and_development_services for required documentation.
Submit your application online at https://permits.cityoftacoma.org/ or in person at the City of Tacoma Planning and Development Services — Building.
Pay the permit fee: $1,000–$5,000.
Wait for plan check approval. Estimated timeline: 3-6 weeks.
Schedule required inspections through https://permits.cityoftacoma.org/. All inspections must pass before project is finalized.
Important: Tacoma Planning. Washington HB 1337 requires ministerial ADU processing. Up to 2 ADUs per lot. TPU utility connection fees for new ADU electric service.
City of Tacoma Planning and Development Services — Building
Phone: (253) 591-5030
Website: https://www.cityoftacoma.org/government/city_departments/planning_and_development_services
Online Permits: https://permits.cityoftacoma.org/
Hours: Mon-Fri 8:00am-4:30pm
Frequently Asked Questions
Can I build an ADU on my Tacoma property?
Yes. Washington HB 1337 (2023) requires Tacoma to allow at least 2 ADUs per single-family lot by-right, without owner-occupancy requirements. ADUs are limited to 1,000 sqft. No owner-occupancy requirement. Tacoma has updated its Municipal Code to comply with state law. The permit must be processed ministerially. Contact Tacoma Planning and Development Services for specific requirements.
How does Tacoma's housing market compare to Seattle?
Tacoma's housing is significantly more affordable than Seattle — median home prices are roughly 25-35% lower. Tacoma is in the Seattle-Tacoma-Bellevue MSA and many residents commute to Seattle via Sound Transit's Sounder commuter train or light rail. This makes Tacoma attractive for buyers priced out of Seattle. The downtown has undergone significant revitalization with museums (Museum of Glass, Tacoma Art Museum), restaurants, and the University of Washington Tacoma campus.
What is Joint Base Lewis-McChord and how does it affect Tacoma's housing?
Joint Base Lewis-McChord (JBLM) is a combined Army (Fort Lewis) and Air Force (McChord Air Force Base) installation located adjacent to Tacoma, making it one of the largest military installations on the West Coast. JBLM has approximately 40,000 active duty personnel plus families — creating enormous housing demand in Tacoma and Pierce County. Military housing allowances often support higher rental rates in Tacoma neighborhoods near transit routes to JBLM. For ADU investors, JBLM creates stable rental demand.
Who provides electricity in Tacoma?
Most of Tacoma is served by Tacoma Public Utilities (TPU), a city-owned utility. This distinguishes Tacoma from areas served by Puget Sound Energy. TPU rates are generally competitive and the city-owned structure can be more flexible on solar interconnection. For solar installations, you'll need an electrical permit from Tacoma Planning and an interconnection agreement with TPU. Some Tacoma areas near city limits may be served by Puget Sound Energy — verify your service provider.
What should I know about Tacoma's hillside neighborhoods?
Tacoma has many neighborhoods on hills with views of Puget Sound and Mount Rainier. These hillside neighborhoods (North End, Proctor District, Stadium District) are highly desirable but come with geologically hazardous area designations on many properties. Landslide risk affects some hillside lots — geological reports may be required for building permits near steep slopes. Tree removal near steep slopes requires additional review. The views are spectacular but the slopes require careful due diligence before construction.
Source: Tacoma Building Code — ADU (Accessory Dwelling Unit) Requirements. Last verified April 6, 2026. View source