Definition
The California Density Bonus Law (Government Code § 65915 et seq.) provides qualifying housing developers with a legal entitlement to exceed local zoning density limits — measured in units per acre or similar metrics — in exchange for including a specified percentage of deed-restricted affordable units in their project. The bonus is mandatory and ministerial: if a project qualifies, the agency must grant it and cannot condition it away.
How the Bonus Is Calculated
The density bonus is calculated as a percentage increase above the "base density" — the maximum density otherwise permitted by local zoning. The percentage depends on how much affordable housing the applicant provides:
- Projects providing 5% of units for very low-income households receive approximately a 22.5% density bonus.
- Projects providing 10% of units for low-income households receive approximately a 20% bonus.
- Projects providing 10% of units for moderate-income households (for-sale projects only) receive approximately a 5% bonus.
- The maximum density bonus reaches 50% for projects with higher affordable percentages, and there is no density cap for 100% affordable projects — they receive unlimited additional density.
Note: Government Code § 65915 has been amended frequently — the bonus percentages above reflect the general structure but the exact graduated schedule changes with each legislative session. Always apply the current enrolled version of the statute when evaluating a specific project.
Incentives and Waivers
Beyond the density bonus itself, qualifying projects are also entitled to:
- Incentives or concessions: Reductions in development standards (setbacks, parking, open space requirements, lot coverage) that would otherwise reduce the project's financial feasibility. The agency must grant at least one incentive unless it makes specific findings that the incentive would have an adverse impact on health, safety, or the physical environment.
- Waivers or reductions of development standards: An applicant may request a waiver of any development standard that would physically prevent the development from achieving the density or number of units called for by the density bonus. The agency cannot deny the waiver unless it would have a specific, adverse impact on public health or safety that cannot be mitigated.
Parking Reductions
Density bonus projects also qualify for reduced parking standards. For projects within one-half mile of a major transit stop, the agency may not impose any parking requirement at all — regardless of local zoning. This is one of the most practically significant density bonus provisions for transit-adjacent urban infill projects.
What Agencies Cannot Do
Agencies may not:
- Deny a density bonus to a qualifying project on any ground other than that the project does not in fact qualify
- Impose conditions that would have the effect of reducing the number of units below the density bonus calculation
- Apply local design standards in a way that renders the project economically infeasible or prevents it from achieving the bonus density
- Require additional CEQA review as a condition of granting the bonus or related incentives (bonus units do not independently trigger CEQA)
Density Bonus Law compliance is one of the most frequently litigated areas of California housing law. Agencies that impose standards that effectively prevent a qualifying project from achieving its entitled density face HAA exposure. Legislaide helps planning departments implement density bonus review workflows that protect the agency from challenge.
Frequently Asked Questions
What is a density bonus?
California's Density Bonus Law (Government Code § 65915) provides qualifying housing developers a mandatory right to exceed local zoning density limits — building more units than otherwise allowed — in exchange for including deed-restricted affordable units. The bonus is ministerial: agencies cannot deny it if the project qualifies.
How is the density bonus calculated?
The bonus is a percentage increase above the base density allowed by local zoning. Projects providing 5% of units for very low income households receive approximately a 22.5% bonus; higher affordable percentages yield larger bonuses up to 50%. 100% affordable projects receive unlimited additional density.
What are incentives and concessions under the Density Bonus Law?
Qualifying projects are also entitled to incentives or concessions — reductions in development standards like setbacks, parking, or open space requirements — if needed for financial feasibility. The agency must grant at least one incentive unless it makes specific findings that it would adversely impact public health, safety, or the physical environment.
Can a city deny a density bonus to a qualifying project?
No. The density bonus is a ministerial entitlement. If the project qualifies, the agency must grant it and cannot deny or reduce it based on neighborhood character, zoning inconsistency, or any ground other than that the project does not actually meet the statutory eligibility criteria.
What parking reductions apply to density bonus projects near transit?
For density bonus projects within one-half mile of a major transit stop, the agency may not impose any minimum parking requirement at all. This is among the most significant cost-reduction tools for transit-adjacent urban infill projects using the Density Bonus Law.
Published April 1, 2026 by Legal Team at Legislaide.