Union City, CA Accessory Structures: ADU Rental Restrictions (2026)
Key Facts
- Minimum rental term
- 30 days
- Applies to
- All permitted ADUs
- Short-term platforms
- Effectively barred
- Related rule
- ADU can't be sold separately
Summary
Union City bans renting an accessory dwelling unit for less than 30 days, closing the door on Airbnb-style short-term rentals for every ADU permitted under the city's zoning code.
Short-Term Rental Limitation. ADUs shall not be rented for a term of less than 30 days.
K. Utility Connection. ADUs constructed within the proposed space of a primary dwelling or existing space of a primary dwelling unit or accessory structure shall not be required to install a new or separate utility connection directly between the ADU and the utility or impose a related connection fee or capacity charge, unless the ADU was constructed with a new single-family dwelling, or upon separate conveyance of the ADU pursuant to Government Code Section 66341. (Ord. 2025-002, 3/25/2025)
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4940544; v16 updated 2026-06-23).
Full Breakdown
Union City bars short-term rentals of accessory dwelling units: under Union City Municipal Code § 18.34.030(J), an ADU cannot be rented for a term of less than 30 days, closing off nightly or weekly rental platforms for these units citywide. The restriction applies to every ADU permitted under Chapter 18.34, regardless of district, and sits alongside the separate-sale ban in subsection (H), which keeps an ADU from being conveyed apart from the primary dwelling except as state law allows under Government Code Section 66341.
Violations & Fines
Renting a Union City ADU for stays under 30 days violates § 18.34.030(J) and is a zoning code violation subject to code enforcement citation and civil penalties under the City's general enforcement provisions.
Frequently Asked Questions
Can I list my Union City ADU on a short-term rental platform?
Does the 30-day rental minimum apply to every ADU in Union City?
Sources & Official References
Other rules in Union City
California rules heatmap·Compare Union City to another location·View the California accessory structures overview
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ADU Rental Restrictions in Nearby Cities
How other cities in Alameda County handle adu rental restrictions.