Informational only, not legal advice. ADU rules change often and differ by city. Confirm with your local planning department before you rely on anything here.
California voters rejected Proposition 45 on November 3, 2026. The initiative, titled "Modifies Environmental Review for Certain Projects," would have given "essential" projects, with housing near the top of the list, a faster track through the California Environmental Quality Act (CEQA). When KQED called the race on November 7, No led 56.2% to 43.7%, about 6.5 million votes to 5.1 million. For anyone building an ADU, splitting a lot under SB 9 or subdividing under SB 684, the result changes nothing, because those approvals already skip CEQA.
If you are planning an ADU, a JADU, an SB 9 lot split or an SB 684 starter-home subdivision, Prop 45 failing does not slow you down. Those approvals are ministerial: the city checks your plans against objective rules and must say yes if they comply. CEQA never applied. Bigger infill projects still have the AB 130 exemption that took effect July 1, 2025. Whether a specific site qualifies depends on its zoning and conditions, so confirm with your city before you design around it.
What Prop 45 would have done
According to the Legislative Analyst's Office, Prop 45 created an optional set of procedures for eligible projects. An applicant could choose them or stay with today's process. The main changes:
- Hard deadlines. Binding time limits for completeness checks, permits and the environmental impact report (EIR), including a 365-business-day limit to finish an EIR, with the right to a hearing and possibly a lawsuit if an agency missed it.
- Fixed rules. Impacts judged by the laws and standards in place on the day the application was filed.
- One alternative. The applicant, not the agency, could propose a single project alternative.
- Narrower lawsuits. A court that found a CEQA error could stop only the flawed part of a project while it was fixed, not the whole thing.
The LAO estimated start-up costs for state and local government in the high tens of millions of dollars a year, potentially over $100 million, partly covered by fees. Opponents argued it went much further than the Legislature's recent reforms. Voters agreed with them.
Does CEQA apply to ADUs? No, and Prop 45 never touched that
CEQA applies to discretionary decisions, where an agency weighs a project and could say no. It does not apply to ministerial approvals, where staff check a plan against fixed standards. State ADU law puts ADUs squarely in the second group. Government Code section 66317 says a compliant ADU application must be approved ministerially, without a hearing, within 60 days when a home already exists on the lot.
The same logic covers the lot-level pathways we work with:
| Pathway | How it is approved | CEQA review? |
|---|---|---|
| ADU / JADU | Ministerial, 60 days | No |
| SB 1211 multifamily ADUs | Ministerial | No |
| SB 9 lot split + two units | Ministerial | No |
| SB 684 / SB 1123 small-lot subdivision | Ministerial | No |
| Larger infill apartments | Depends on zoning and site | Often exempt under AB 130 |
So the failed measure would have mattered most for projects that still face discretionary review: large apartment buildings needing a zone change, master-planned subdivisions, and infrastructure. That is a real loss for those projects, but not for a backyard cottage. If your city tells you an ADU or SB 9 project needs an environmental study, that is a red flag worth pushing back on; our guide to the ADU permit process covers what a city can and cannot ask for.
The CEQA reforms that are still law: AB 130 and SB 131
The housing world already got a large share of what Prop 45 promised, just through the Legislature. On June 30, 2025, Governor Newsom signed AB 130 and SB 131, two budget trailer bills that took effect July 1, 2025.
AB 130: the infill housing CEQA exemption
AB 130 added Public Resources Code section 21080.66, a statutory CEQA exemption for urban infill housing that is consistent with the general plan and zoning and avoids sensitive and hazardous sites. It comes with tribal consultation steps. For a mid-size apartment project on an infill lot, this is the tool that removes the EIR that Prop 45 was trying to speed up.
SB 131: the "near miss" rule
SB 131 covers projects that would be exempt except for one condition. Instead of a full review, CEQA analysis is limited to the effects of that single condition. San Mateo County's planning department, among others, now walks applicants through both laws on a checklist.
Neither law was on the ballot, and the Prop 45 result does not repeal them.
How this fits with SB 9, SB 684 and SB 79
For a single-family lot, the order of operations has not changed. Start with what is ministerial: up to two ADUs plus a JADU (see the two-ADU rule), or an SB 9 lot split with up to two units per half. If the lot is larger or in a multifamily zone, look at SB 684 and SB 1123 for up to 10 small homes, still ministerial.
Near transit, SB 79 raises the zoning envelope. A project built to that zoning may be able to use the AB 130 exemption, but that is a site-by-site call that depends on the lot's history, hazards and size. Not legal advice; a land-use attorney should confirm it for your lot.
Our take
Prop 45 was a fight about big projects. The small-lot pathways that most homeowners and small builders use were built by the Legislature to avoid CEQA entirely, and they still do. If you have been waiting on the election before starting an ADU or lot split, there is nothing left to wait for. Run your address through Parcy to see which pathways your lot qualifies for, then check your city's ADU ordinance for the local objective standards.
Frequently asked questions
Did Prop 45 pass in California?
No. Proposition 45 failed on November 3, 2026, with about 56% voting no and 44% voting yes in the count when the race was called on November 7. Final results are certified by the Secretary of State in December.
Does CEQA apply to ADUs in California?
Generally no. State law requires cities to approve a compliant ADU ministerially, and CEQA does not apply to ministerial approvals. Your city can still enforce objective rules such as setbacks and height.
Is an SB 9 lot split subject to CEQA?
No. SB 9 lot splits and two-unit projects are approved ministerially, so they do not go through CEQA review. Local objective standards and the eligibility conditions in the law still apply.
What CEQA reforms are still in effect after Prop 45 failed?
AB 130 and SB 131, signed June 30, 2025, remain law. AB 130 created a CEQA exemption for qualifying urban infill housing, and SB 131 limits review for projects that miss an exemption by a single condition.
Official bill text
- AB 130 — Housing. (official bill text, California Legislative Information)
- SB 131 — Public Resources. (official bill text, California Legislative Information)
- SB 9 — Housing development: approvals. (official bill text, California Legislative Information)
Sources
- Legislative Analyst's Office: Proposition 45 analysis (November 3, 2026 ballot) — What the measure would have done, 365-business-day EIR limit, fiscal effects
- Secretary of State: Official Voter Information Guide, Proposition 45 — Ballot label, arguments for and against
- KQED election results: Proposition 45 — Yes 43.7%, No 56.2%; race called November 7, 2026
- County of San Mateo Planning: AB 130 and SB 131 — Signed June 30, 2025, effective July 1, 2025; infill exemption and near-miss review
- Public Resources Code section 21080.66 (infill housing CEQA exemption) — Statutory text of the AB 130 exemption
- Government Code section 66317 (ministerial ADU approval) — ADU applications approved ministerially, 60-day deadline
- Prop 45
- Proposition 45 results
- Prop 45 CEQA
- does CEQA apply to ADUs
- CEQA exemption for SB 9 lot split
- AB 130 infill housing CEQA exemption
- CEQA housing reform California 2026
- ministerial approval ADU
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Informational only. Not legal, architectural, or investment advice. Confirm current rules with your local planning department.