Every California city has a state housing goal it has to plan for by 2029. Most Orange County cities are nowhere close. Anaheim, Fullerton, Garden Grove, Costa Mesa, Tustin and Newport Beach have each permitted less than 20% of their target, with about three years left.
That sounds like a city hall problem. If you’re buying a property to add an ADU, it’s leverage. Here’s the data, and why it works in your favor.
The scoreboard: OC cities vs. their 2029 housing goals
The state assigns each city a number of homes to plan for under the Regional Housing Needs Allocation (RHNA). For Orange County’s current cycle, the period runs to October 15, 2029. The goals below are from SCAG’s final 6th cycle RHNA allocation plan. Units permitted are from Voice of OC’s April 2026 review of city housing filings.
| City | Units permitted | 2029 goal | % complete |
|---|---|---|---|
| Santa Ana | 4,757 | 3,137 | 152% |
| Anaheim | 3,048 | 17,453 | 17.5% |
| Garden Grove | about 2,300 | 19,168 | 12.0% |
| Huntington Beach | about 1,500 | 13,368 | 11.2% |
| Fullerton | 1,384 | 13,209 | 10.5% |
| Tustin | about 540 | 6,782 | about 8% |
| Newport Beach | 352 | 4,845 | 7.3% |
| Costa Mesa | 643 | 11,760 | 5.5% |
Santa Ana is the only large OC city on track. HCD’s own progress data paints the same picture for the rest of my coverage area: Buena Park about 4%, Westminster about 9%, Orange about 21% and Stanton about 25%.
Now look at the pace. According to HCD permit data, Fullerton permitted 616 housing units in 2025. At that rate, closing its remaining gap of about 11,800 units would take roughly 19 years. Garden Grove would need about 26 years. Costa Mesa, at 232 units in 2025, would need more than 45 years. None of them are going to make it by 2029.
ADUs are what these cities actually build
Every city files an Annual Progress Report with the California Department of Housing and Community Development (HCD). Every ADU permit goes into that report and counts toward the city’s RHNA number. Many OC cities also count a share of ADUs as lower-income units, based on SCAG’s ADU affordability study, which helps with the hardest part of their goal.
I pulled the raw permit data from HCD’s Annual Progress Report dataset (Table A2) for 2021 through 2025. Here’s how much of each city’s new housing was ADUs:
| City | ADU permits, 2021–2025 | All housing units permitted | ADU share |
|---|---|---|---|
| Westminster | 908 | 996 | 91% |
| Garden Grove | 1,906 | 2,374 | 80% |
| Newport Beach | 233 | 381 | 61% |
| Costa Mesa | 374 | 636 | 59% |
| Orange | 400 | 967 | 41% |
| Buena Park | 171 | 418 | 41% |
| Fullerton | 509 | 1,448 | 35% |
| Stanton | 144 | 410 | 35% |
| Huntington Beach | 437 | 1,317 | 33% |
| Anaheim | 1,110 | 3,513 | 32% |
| Santa Ana | 953 | 5,015 | 19% |
| Tustin | 62 | 551 | 11% |
In Westminster and Garden Grove, ADUs are close to the whole housing pipeline. In Costa Mesa and Newport Beach, they’re more than half of it. Large apartment projects stall over financing and politics. Backyard ADUs keep getting built one lot at a time.
A planning department that is 88% short of its goal has no reason to slow-walk the one product that keeps showing up in its report. For what ADU homes are selling for in those two cities, see my Garden Grove October 2026 market update and the Westminster fall 2026 report.
Why the state is watching closely
Being behind on RHNA isn’t illegal on its own. Failing to plan for housing is, and the state now has real enforcement tools.
The clearest local example is Huntington Beach. On May 15, 2026, a court ordered the city to pay $160,000 in penalties plus $50,000 a month starting in June 2026 until it adopted a compliant housing element, according to the California Attorney General’s office. The city council approved a housing element the following month.
That case was about the city’s housing plan, not ADUs. But it shows every OC planning department that Sacramento will go to court and collect. A city in that position does not want an ADU denial that HCD could flag as a violation of state ADU law.
What state ADU law already guarantees you
These rules apply in every OC city, whether it’s ahead or behind. The pressure above just makes cities less likely to push back on them. HCD’s ADU Handbook lays out the full list.
- Ministerial approval. A compliant ADU is approved by staff, with no public hearing and no neighbor vote.
- 15 business days to call it complete. Under SB 543, effective January 1, 2026, the city must review your application and send a list of anything missing within 15 business days. Resubmittals get the same 15-day clock.
- 60 days to approve or deny. Once the application is complete, the city has 60 days to act. A denial has to come in writing with the specific problems and how to fix them.
- Local rules must be filed with the state. Under SB 9 (2025), a different bill from the 2021 lot-split law, a local ADU ordinance that isn’t submitted to HCD is void, and the city has to follow state standards until it complies.
- More units allowed. AB 956 now allows two detached ADUs on many single-family lots, and SB 1117 removes the impact fee cliff at 750 sq ft. I covered both in this breakdown of the new ADU laws.
What it doesn’t mean
I don’t want to oversell this. A city being behind on housing goals does not let you skip building code, fire access, the setbacks state law still allows, or utility requirements. Utility hookups are still the most common hidden delay, and SB 1196 is only now addressing them. Lot size and layout still decide what fits. In Costa Mesa, for example, lot size drives your options.
What changes is the tone of the process. In a city that needs every unit it can report, a clean, code-compliant ADU application is the easiest win staff will see all week.
How I’d rank my OC cities for ADU buyers
Proven ADU volume, far behind on goals
Garden Grove and Westminster. Garden Grove has issued 370 to 430+ ADU permits a year since 2022, and Westminster about 190 to 215 a year since 2023. ADUs make up most of their housing production. Their staff process ADUs every day.
Rising ADU numbers
Fullerton, Buena Park and Anaheim. Fullerton’s ADU permits went from 110 in 2024 to 168 in 2025. Buena Park went from 29 to 58. Anaheim has issued 240 to 280 a year since 2023. All three are at 17.5% of their goal or lower.
Low overall production, ADUs carry the load
Costa Mesa, Newport Beach and Huntington Beach. Costa Mesa is at 5.5% of its goal and ADUs are 59% of what it permits. Higher land prices make these deals harder to pencil, but the permit side is in your favor.
The exceptions
Santa Ana is already past its total goal, so it faces less pressure overall, though it still permitted 258 ADUs in 2025. Orange and Stanton are further along than most at 21% to 25%, and Stanton is a small city with a 1,231-unit goal.
If your ADU permit stalls or gets denied
- Track the dates. Write down when you submitted and when the city responded. If 15 business days pass with no completeness letter, or 60 days pass after the application is complete, say so in writing.
- Ask for the written reasons. A denial must list the defects and how to fix them. Most denials are fixable plan corrections.
- Check the city’s rule against state law. If a local requirement goes beyond the state ADU statute, cite the HCD Handbook.
- Use HCD’s technical assistance portal. HCD’s ADU page links to a portal that accepts ADU questions and violation reports from the public.
For the full process, read what happens when your Orange County ADU application is denied. Better yet, avoid the problem before you buy. Here’s how to verify ADU potential while you’re in escrow.
The bottom line
Most OC cities have permitted less than 20% of their 2029 housing goal, and ADUs are a large share of what they do permit: 80% in Garden Grove, 91% in Westminster. The state is enforcing housing law with real money, and state ADU law puts cities on a 15-business-day and 60-day clock. Every ADU you build helps a city that’s behind. That gives a well-prepared buyer leverage. Before you build, run the numbers on how you’ll finance the ADU.
If you’re buying a property in Orange County or LA County to add an ADU and want to know how the city will treat your specific lot, call Dylan Serna, ADU Realtor at 714-860-2868.
Dylan Serna | The ADU Realtor | eXp Realty | DRE #02217359
This post is general information, not legal advice. Housing goal figures come from SCAG’s 6th cycle RHNA allocation, Voice of OC’s April 2026 review and HCD progress data. ADU permit counts are from HCD Annual Progress Report data as reported by each city for calendar years 2021–2025 and may differ slightly from city totals. ADU laws and local rules change. Confirm requirements with your city and talk to a land use attorney before relying on any of this for a specific property.
