Do Some California Cities Require School Impact Fees for ADUs?

School Impact Fees and Your ADU Project

When planning your ADU project in California, most homeowners focus on construction costs, permit fees, and utility connections. But there is one fee category that catches many homeowners off guard: school impact fees. These fees, also known as school facility fees or developer fees, are charged by school districts to fund new school construction and facility improvements necessitated by new residential development.

The question of whether school impact fees apply to ADUs is surprisingly complex. California state law has established clear rules about impact fees for ADUs, but the application of school fees specifically has been a source of confusion and even controversy in many jurisdictions. In this comprehensive guide, we will break down everything you need to know about school impact fees and ADUs in California.

Understanding these fees is important because they can add $2,000 to $10,000 or more to your project costs, depending on the size of your ADU and the school district's fee schedule. Knowing whether you are exempt and how to budget for these fees can significantly affect your project's financial viability.

What Are School Impact Fees?

School impact fees are one-time charges assessed on new residential construction to help fund school facilities. California Education Code Sections 17620 through 17626 authorize school districts to levy these fees on new residential and commercial/industrial development within their boundaries.

The fees are based on the square footage of new habitable space being added. The California State Allocation Board sets maximum fee amounts that school districts can charge, and these amounts are updated periodically. As of 2026, the maximum Level 1 school impact fee for residential construction is approximately $4.79 per square foot (this amount is adjusted for inflation).

How School Impact Fees Are Calculated

ADU Size	Level 1 Fee (approx.)	Level 2 Fee (if applicable)	Level 3 Fee (if applicable)
400 sq ft	$1,916	$3,200	$4,800
600 sq ft	$2,874	$4,800	$7,200
800 sq ft	$3,832	$6,400	$9,600
1,000 sq ft	$4,790	$8,000	$12,000
1,200 sq ft	$5,748	$9,600	$14,400

Note: Level 2 and Level 3 fees require the school district to meet specific criteria under Government Code Sections 65995.5 and 65995.7. Most ADU projects will only be subject to Level 1 fees if applicable at all.

ADU Exemptions from School Impact Fees

This is where it gets important for ADU homeowners. California Government Code Section 65852.2(f)(3) provides critical protections regarding impact fees for ADUs:

ADUs Under 750 Square Feet: Exempt

California law prohibits any impact fees (including school impact fees) on ADUs that are 750 square feet or less. This is a blanket exemption that applies statewide, regardless of what the local school district or city says. If your ADU is 750 square feet or smaller, you should not be charged school impact fees.

ADUs Over 750 Square Feet: Proportional Fees

For ADUs larger than 750 square feet, impact fees must be charged proportionally to the relationship between the ADU's square footage and the primary dwelling's square footage. This means the school district cannot charge the same fee they would charge for a full-sized new home. The proportional calculation typically results in significantly reduced fees compared to standard new construction rates.

Garage Conversions: Often Exempt

ADUs created by converting existing space (such as a garage conversion) may be exempt from school impact fees because you are not adding new square footage to the lot. However, this exemption varies by jurisdiction. Some school districts argue that converting non-habitable space to habitable space triggers the fee. Check with your local school district for their specific policy.

How Different California Cities Handle School Fees

The application of school impact fees to ADUs varies significantly across California. Here is a sampling of how different jurisdictions handle this issue:

Los Angeles Unified School District (LAUSD)

LAUSD does charge school impact fees on new ADU construction over 750 square feet. The fee is calculated based on the net new habitable square footage. For ADUs under 750 square feet, no school impact fee is charged, consistent with state law. LAUSD has a separate fee schedule from the City of Los Angeles building permit fees, and you will typically receive a separate clearance letter from LAUSD during the permit process.

San Diego Unified

San Diego has generally followed state law by exempting ADUs under 750 square feet and charging proportional fees for larger units. The city has been proactive in clarifying its fee schedule for ADU projects.

San Francisco

San Francisco has a unique approach because of its combined city-county structure. School impact fees for ADUs are handled through the city's development fee process, and exemptions for smaller ADUs apply.

Smaller Cities and Unincorporated Areas

Smaller cities and unincorporated areas served by smaller school districts may have different interpretations. Some school districts have adopted policies explicitly exempting all ADUs from school impact fees, while others charge fees even on units that may qualify for exemptions under state law.

Jurisdiction	ADUs Under 750 sq ft	ADUs Over 750 sq ft
LAUSD area	Exempt	Proportional fee
San Diego	Exempt	Proportional fee
San Jose	Exempt	Proportional fee
Many smaller districts	Varies	Varies

How to Challenge Improper School Impact Fees

If you believe your ADU project is being charged school impact fees in violation of state law, you have several options:

Step 1: Request Fee Justification

Ask the school district for a written explanation of the fee, including the legal authority they are relying on. Request documentation showing how the fee was calculated and whether the proportionality requirement was applied.

Step 2: Reference State Law

Point the school district to Government Code Section 65852.2(f)(3), which clearly states that impact fees cannot be imposed on ADUs of 750 square feet or less, and that fees on larger ADUs must be proportional. Also reference the California HCD's published guidance on ADU impact fees.

Step 3: File a Complaint with HCD

If the school district or city insists on charging improper fees, you can file a complaint with the California Department of Housing and Community Development. HCD has been increasingly active in addressing improper fee practices.

Step 4: Consult a Land Use Attorney

For significant fee disputes, consulting with a land use attorney may be worthwhile. The cost of legal representation ($1,500 to $5,000 for a fee dispute) may be justified if the disputed fee is substantial. See our guide on what to do when a city denies your ADU for more information on legal options.

Budgeting for School Impact Fees

When creating your ADU project budget, it is wise to include school impact fees as a line item even if you expect to be exempt. This way, if fees are charged, your budget can absorb them without derailing the project. Here is how to budget for school fees:

• ADUs under 750 sq ft: Budget $0 for school impact fees (you are exempt by state law), but include a $500 contingency for administrative fees
• ADUs 750-900 sq ft: Budget $2,000 to $4,000 depending on your school district's fee schedule
• ADUs 900-1,200 sq ft: Budget $3,000 to $6,000 depending on your school district's fee schedule

Remember that school impact fees are just one component of your total permit and development fees. For a comprehensive look at all ADU costs in California, see our detailed cost guide.

Recent Legislative Changes Affecting School Fees

California's legislature has been actively addressing impact fee issues for ADUs. Several recent bills have strengthened homeowner protections regarding school impact fees. AB 1033 introduced the concept of separate ADU ownership (similar to condominiums), which may affect how school fees are assessed in the future. SB 897 clarified that ADUs should not be treated the same as standard new housing for fee purposes. Additionally, ongoing advocacy by housing organizations continues to push for further fee reductions or eliminations for ADU construction.

The trend in California is clearly toward reducing or eliminating barriers to ADU construction, including excessive fees. Homeowners who are charged fees they believe are improper should not hesitate to challenge them, as the legal landscape increasingly favors homeowner rights in this area.

Frequently Asked Questions

Are school impact fees the same as city permit fees?

No, school impact fees are separate from city building permit fees. City permit fees cover the cost of plan review, inspections, and building department operations. School impact fees go to the school district to fund school construction and improvements. They are typically assessed and collected separately, though in some cities, the building department collects both sets of fees on behalf of the school district.

Can I avoid school impact fees by building my ADU smaller than 750 square feet?

Yes, California law exempts ADUs of 750 square feet or less from all impact fees, including school impact fees. This is one reason why many homeowners choose to design their ADUs at or under the 750-square-foot threshold. The fee savings can be $2,000 to $6,000 or more, which may offset any loss of livable space.

Do JADUs (Junior ADUs) have to pay school impact fees?

Junior ADUs (JADUs), which are created within the existing footprint of the primary home and are 500 square feet or less, are exempt from all impact fees, including school impact fees. Since JADUs do not add new square footage to the property, school districts have no basis for charging development fees.

When do I pay school impact fees during the ADU permitting process?

School impact fees are typically paid at the time of permit issuance, before construction begins. In some jurisdictions, you may receive a separate invoice from the school district, while in others, the building department collects the fee as part of the overall permit fee package. Always ask about school fees early in the process so there are no surprises at permit issuance.

Can school impact fees be financed or paid in installments?

School impact fees are generally due in full at the time of permit issuance. They are not typically available for installment payment. However, you can include these fees in your overall construction financing. If you are using an ADU construction loan, school impact fees can usually be rolled into the loan amount. Check our guide on ADU financing options for more details.

What happens if I pay school impact fees and then my ADU project is cancelled?

If you cancel your ADU project after paying school impact fees, you may be eligible for a refund. Contact the school district directly to request a refund of the fees. Most districts have a policy for refunding unused development fees, though the process may take several weeks. Keep your receipt and permit documentation for the refund request.

How to Check Your City's School Impact Fees for ADUs

Before you begin your ADU project, it is important to understand whether your city charges school impact fees and how much they might add to your total construction cost. Here is a step-by-step guide to finding out what you owe.

Step 1: Contact Your Local School District

School impact fees are set by the local school district, not the city planning department. Call or email your school district's facilities planning office and ask for their current Level 1 developer fee schedule. These fees are typically expressed as a dollar amount per square foot of new residential construction.

Step 2: Check for ADU Exemptions

Under California law, ADUs under 750 square feet are generally exempt from impact fees, including school fees. If your ADU is 750 square feet or larger, fees may apply but must be calculated proportionally based on the ADU's size relative to the primary dwelling. Ask the school district specifically about ADU-related exemptions or reductions.

Step 3: Review Your City's Fee Schedule Online

Many California cities publish their development fee schedules on their planning or building department websites. Look for a section on "development impact fees" or "fee schedules" and search for entries related to ADUs or accessory dwelling units. Some cities have created separate fee categories for ADUs that reflect the proportional fee requirements under state law.

Step 4: Request a Fee Estimate from Your Permit Office

When you submit your ADU permit application, your city's building department will calculate all applicable fees, including school impact fees. You can request a preliminary fee estimate before submitting your formal application. This helps you budget accurately and avoid surprises during the permitting process. For more on the permit process, see our guide on over-the-counter vs. plan check ADU approval.

Step 5: Understand Payment Timing

School impact fees are typically due at the time of permit issuance, before construction begins. Some jurisdictions allow payment at the certificate of occupancy stage, but this is less common. Confirm the payment timeline with your building department so you can plan your project financing accordingly.

Frequently Asked Questions

Are school impact fees the same in every California city?

No. School impact fees vary significantly across California because they are set by individual school districts based on their facility needs. Fees can range from $2 to $5 or more per square foot of new construction. Some districts have not updated their fee schedules in years, while others adjust them annually.

Do I have to pay school impact fees if my ADU is under 750 square feet?

Generally, no. California Government Code Section 65852.2 exempts ADUs under 750 square feet from most impact fees, including school fees. However, it is always wise to confirm this exemption with your local school district, as some may not be fully aware of the state law provisions. If a district attempts to charge fees on a sub-750-square-foot ADU, you can reference the state code and contact HCD for assistance.

Can school impact fees be negotiated or waived?

School impact fees are established by law and are not typically negotiable. However, some school districts offer fee credits if you are replacing an existing structure or if the project provides a community benefit. Additionally, certain affordable housing ADU programs may include fee waivers or reductions. Check with your local school district and city planning office for any available programs.

How much do school impact fees typically add to the cost of an ADU?

For a typical ADU of 800 to 1,200 square feet, school impact fees can range from $2,000 to $8,000 depending on your school district's rate. While this is a relatively small portion of the overall ADU construction cost, it is an expense that homeowners should account for in their budget. For a complete overview of ADU costs, visit our guide on ADU costs in California for 2026.

Do school impact fees apply to garage conversions or JADUs?

Junior ADUs (JADUs) are generally exempt from all impact fees under California law because they are 500 square feet or smaller and located within the existing primary dwelling. Garage conversions that qualify as JADUs also benefit from this exemption. For larger garage conversions that qualify as full ADUs, the standard fee rules based on size apply. Learn more about your options in our article on local ADU rules vs. California state law.