What SB 423 Changes
SB 423 amends Government Code § 65913.4 — the SB 35 ministerial approval statute — to extend California's streamlined multifamily housing approval process through January 1, 2036, eliminate the blanket coastal zone exclusion, and expand the universe of projects and jurisdictions subject to by-right approval. The practical effect: qualifying multifamily housing near transit must receive ministerial approval in virtually every California city and county, including coastal jurisdictions that previously assumed they were exempt.
Ministerial approval means no public hearing, no CEQA review, no discretionary planning commission action. Staff either approve the project because it meets objective standards, or deny it because it does not. There is no middle ground.
Who in City Hall Needs to Read This
| Role | Why This Matters to You |
|---|---|
| Planning Director / Community Development | Primary compliance owner. Must identify which multifamily infill projects qualify for SB 423 ministerial review, update intake procedures and checklists, train planners on objective standards review, and ensure SB 423 applications are routed as ministerial — not scheduled for commission hearings. |
| City Attorney / County Counsel | SB 423 is a Housing Accountability Act statute. Agencies that improperly deny or delay a qualifying project are subject to HAA enforcement — including court orders mandating approval and potential attorney fee awards. Counsel must be prepared to advise on eligibility determinations and defend any denial of a project claiming SB 423 protection. |
| City Manager / CAO | SB 423 changes the political landscape for infill housing. Elected officials cannot lawfully direct staff to slow, condition, or deny qualifying projects through procedural means. Agencies that try to impose de facto discretionary review on SB 423 projects face state enforcement, builder's remedy exposure, and litigation from applicants. |
| Building Official | Projects receiving SB 423 ministerial approval still require building permits and inspections. Coordinate with planning to ensure approved SB 423 projects receive expedited plan check handling consistent with HCD guidance and Permit Streamlining Act timelines. |
| Housing Element Coordinator | SB 423 ministerial approval is linked to RHNA compliance. Agencies out of compliance with their Housing Element may face higher affordability thresholds. Maintain current HCD compliance data to ensure the correct affordability floor is applied to each application. |
Legislation Overview
SB 423 (Wiener) | Chapter 778, Statutes of 2023 | Signed: September 28, 2023 | Effective: January 1, 2024 | Expires: January 1, 2036 | Amends: Government Code § 65913.4
SB 423 dramatically expands the reach of the SB 35 ministerial approval pathway for multifamily housing. The most significant structural changes are the elimination of the coastal zone exclusion and the 10-year extension of the sunset date.
What Changed From SB 35
| Provision | SB 35 (2017) | SB 423 (2023) |
|---|---|---|
| Sunset date | January 1, 2026 | January 1, 2036 (10-year extension) |
| Coastal zone | Excluded entirely | Included, with higher affordability floor for coastal projects |
| Affordability (general) | ≥ 50% affordable for RHNA-compliant cities; ≥ 2/3 for non-compliant | Maintains similar structure; coastal projects must meet higher thresholds |
| Labor standards | Prevailing wages for 50+ unit projects; skilled labor for 75+ units | Thresholds revised; 50+ unit projects also require healthcare benefit coverage |
| CEQA exemption | Yes — ministerial approval is CEQA-exempt | Maintained — still CEQA-exempt |
Project Eligibility: What Qualifies for Ministerial Approval
A project must meet ALL of the following site eligibility requirements:
- Zoning: The site must be zoned for residential use or mixed use with at least two-thirds of square footage designated for residential use.
- Urban infill: The site must be in an urbanized area or urban cluster — not in agricultural areas, very high fire hazard severity zones, or other sensitive resource areas.
- Transit proximity: The site must be within one-half mile walking distance of a major transit stop or a high-quality transit corridor (a route with 15-minute or better peak-hour headways).
- No protected land: The site may not include parcels on wetlands, riparian areas, habitats for special status species, or farmland.
- Tenant protections: The site may not include existing housing occupied in the past 10 years by rent-controlled tenants, low-income tenants, or Section 8 voucher holders — unless units are replaced one-for-one at the same or lower rent.
Affordability Thresholds
| Jurisdiction Status | General Projects | Coastal Zone Projects |
|---|---|---|
| RHNA compliant / Housing Element in compliance | ≥ 50% of units at specified affordability levels | ≥ 60% of units affordable |
| Not meeting RHNA / Housing Element non-compliant | ≥ 2/3 of units at specified affordability levels | ≥ 2/3 of units affordable |
Affordability thresholds are calculated on total units. The income targeting within the affordable units is specified by statute — agencies may not substitute their own local income targeting requirements.
What 'Ministerial Approval' Means in Practice
Agencies may still require: Compliance with objective zoning standards (setbacks, height, FAR if objectively stated), building code compliance, ministerial permits, and payment of standard impact fees. Objective design standards are permissible so long as they do not preclude the project from meeting the affordability and density minimums.
Agencies may NOT impose: Architectural review hearings, planning commission discretionary review, conditional use permits as a precondition, additional CEQA documentation, or subjective design criteria that require neighbor or commission approval.
Coastal Zone: The Major New SB 423 Exposure
The single largest change SB 423 made from SB 35 is the elimination of the coastal zone exclusion. Under SB 35, coastal zone projects were entirely exempt. Under SB 423, coastal projects qualify for ministerial approval if they meet all standard eligibility criteria plus a higher affordability floor.
This affects dozens of California cities and counties — including many Bay Area and Southern California coastal cities — that previously assumed their coastal designation insulated them from streamlined multifamily approval. Coastal cities that have not updated their planning processes since January 1, 2024 may be routing SB 423-eligible applications through discretionary review unlawfully.
SB 423 does not override the Coastal Act — projects in the coastal zone still require a coastal development permit (CDP). Coastal cities should establish a dual-track intake process: ministerial SB 423 approval on the planning side, with concurrent CDP routing to the appropriate coastal authority.
Labor Standards for Qualifying Projects
Applicants must certify compliance with labor requirements — the agency is not responsible for enforcement, but should receive and retain labor certifications:
- All qualifying projects: Must use a skilled and trained workforce for specified trades, or pay prevailing wages to all workers.
- 50+ unit projects: Prevailing wages required. Contractor must provide qualifying healthcare coverage to employees.
Compliance Risk Assessment
| Risk | Requirement | Consequence of Non-Compliance |
|---|---|---|
| HIGH | Applying discretionary review to qualifying projects | Routing an SB 423-eligible project through planning commission, design review, or conditional use permit hearings is a Housing Accountability Act violation. Applicants may seek a writ of mandate; courts must award attorney fees to prevailing applicants. |
| HIGH | Treating coastal projects as SB 423-exempt | The SB 35 coastal exclusion does not exist in SB 423. Coastal zone projects meeting eligibility criteria must receive ministerial approval. Agencies still applying the old SB 35 coastal exemption are potentially violating SB 423 for every qualifying application received after January 1, 2024. |
| HIGH | Applying CEQA review to qualifying projects | Ministerial approvals under SB 423 are categorically CEQA-exempt. Requiring an EIR, initial study, or MND for a qualifying project constitutes a de facto denial. No CEQA documentation should be required or requested for SB 423 ministerial approvals. |
| MEDIUM | Using subjective design standards as denial basis | Objective design standards are permissible, but standards requiring commission approval of aesthetics or neighborhood compatibility are not objective. Using such standards to deny or condition SB 423 projects constitutes impermissible discretionary review. |
| MEDIUM | Failure to update intake procedures | Applications for multifamily infill near transit should be screened at intake for SB 423 eligibility. Systemic routing failures — not just one-off errors — create agency-wide process violations. |
| LOW | Inaccurate RHNA compliance tracking | The correct affordability threshold depends on RHNA compliance status. Incorrect tracking could result in applying the wrong threshold — either under- or over-counting affordability requirements. |
Key Dates and Implementation Timeline
| Date | Event / Obligation |
|---|---|
| Sept 28, 2023 | Governor signs SB 423 (Chapter 778, Statutes of 2023) |
| Jan 1, 2024 | SB 423 takes effect — coastal zone exclusion eliminated, extended sunset applies, expanded eligibility operative |
| Jan 1, 2024 onward | All qualifying multifamily infill projects near transit must receive ministerial approval — including in coastal zone jurisdictions |
| Current (2026) | Agencies should audit any denials or delays of coastal-zone multifamily applications since Jan 1, 2024 for potential HAA exposure |
| Jan 1, 2036 | SB 423 sunsets — unless extended by future legislation |
Action Checklist
Immediate — Complete Now
- Planning Department: Audit all multifamily applications received since January 1, 2024 near transit corridors to determine whether any were incorrectly routed through discretionary review.
- Coastal jurisdictions: Immediately discontinue applying the old SB 35 coastal zone exclusion. Update intake checklists and application routing accordingly.
- City Attorney: Review any denials of coastal zone multifamily infill projects since January 1, 2024 for potential HAA exposure; advise on whether remedial action is warranted.
- Planning Department: Create an SB 423 eligibility checklist for use at intake — covering transit proximity, site zoning, affordability commitments, and disqualifying site conditions.
- City Manager: Brief elected officials that SB 423-qualifying projects are ministerial approvals — council cannot direct staff to apply discretionary review, schedule commission hearings, or otherwise delay qualifying applications.
Near-Term — By June 30, 2026
- Planning Department: Identify and update or repeal local design standards or zoning overlays that impose subjective review criteria on multifamily infill.
- Planning Department: Train all planning staff on SB 423 eligibility determination and the boundary between permissible objective standards review and impermissible discretionary review.
- Housing Element Coordinator: Confirm current RHNA compliance status so the correct affordability threshold is applied to all SB 423 applications.
- Coastal jurisdictions: Establish a dual-track intake process for qualifying coastal projects: (1) ministerial SB 423 approval on the planning side, (2) concurrent CDP application routing to the appropriate coastal authority.
Frequently Asked Questions
Does SB 423 apply to all cities, or only those that failed to adopt a Housing Element?
SB 423 applies to virtually all California cities and counties. Housing Element non-compliance affects the affordability threshold (non-compliant jurisdictions face the higher 2/3 requirement rather than 50%), but does not determine whether SB 423 applies at all. Both compliant and non-compliant jurisdictions must provide ministerial approval for qualifying projects.
Can the planning commission weigh in on an SB 423 project — even informally?
No. Routing a ministerial SB 423 application through planning commission review — even informally, even for 'informational' discussion — creates a procedural record that may be characterized as discretionary review. Ministerial approvals must be issued by staff based on objective standards alone.
What happens if we deny an SB 423 project and the developer sues?
The developer may file a petition for writ of mandate in superior court. Under the Housing Accountability Act, courts must award attorney fees to prevailing applicants. SB 423 includes a very short cure window — if the agency issues a written denial with detailed findings, there is a limited opportunity to correct the denial. However, any correction must actually grant ministerial approval — not substitute a new discretionary condition.
Does SB 423 apply to 100% market-rate projects?
No. SB 423 requires that a qualifying percentage of the project's units be affordable — at least 50% (or 2/3 if the jurisdiction is RHNA non-compliant) for most jurisdictions. A 100% market-rate project does not qualify for SB 423 ministerial approval, even if the site and location criteria are met.
SB 423's elimination of the coastal zone exclusion is the single most consequential change for California planning departments in 2024. Agencies that have not updated their processes face compounding HAA exposure for every qualifying application misrouted since January 1, 2024. Legislaide helps coastal cities establish the dual-track intake and objective standards frameworks they need to comply.
Published March 15, 2026 by Legal Team at Legislaide.