ADU fees in Santa Cruz: $12,785–$21,165 for a 1,000 sq ft backyard unit
The City of Santa Cruz prices ADU building permits from valuation ($220 per sq ft for wood-frame homes). It adds trade-permit percentages, a 6% technology surcharge and a reduced General Plan fee for ADUs. Above 750 sq ft, public-safety and child-care impact fees apply.
15 fee lines · 2 official sources · checked Oct 18, 2026 · Sources · Calculator
Modeled fees by ADU size
Detached ADU, 2,000 sq ft main home (example assumption), law in force today. Bars: solid = fees that apply, hatched = fees that may apply.
Each fee with its official source (numbers link to the source list). Est. = computed by us from the official rate; May apply = high total only; Up to = statewide cap, district may charge less.
Fee
499 sq ft
750 sq ft
1,000 sq ft
1,200 sq ft
Planning & zoning
Planning plan check ($401 + $4 per $1,000 valuation)1
Est.$840
Est.$1,061
Est.$1,281
Est.$1,457
General Plan maintenance fee for ADUs (0.61% of valuation)1
Est.$670
Est.$1,006
Est.$1,342
Est.$1,610
Building permit & plan check
Building permit (valuation table)1Valuation = ADU sq ft × $220.00, the City's R-3 rate for wood-frame (type V) construction. From $100,000 valuation: $2,132 + $3 per extra $1,000 (or fraction).
Technology surcharge (6%)16% on building and planning fees. Not charged on impact fees, the General Plan fee or the Green Building fee (which is exempt from CPI and listed separately).
$245
$272
$299
$321
Construction taxes
Parks & recreation facilities tax ($3 per sq ft)1An excise tax on new residential dwelling units (SCMC 5.72), not an impact fee, so the 750 sq ft exemption doesn't cover it. The schedule doesn't say how it applies to ADUs, so it counts toward the high total only.
Childcare impact fee1$0.633 per sq ft, capped at $388 per bedroom. Any ADU above 750 sq ft is past the 614 sq ft cap, so we use $388 for one bedroom.
Exempt
Exempt
Est.$388
Est.$388
School district fee
School impact fee (Santa Cruz City Schools)3The City's ADU page puts the school fee at "around $3.15/square foot" and describes ADUs under 750 sq ft as below the threshold. State law exempts ADUs under 500 sq ft. We show the statewide Level 1 maximum as an upper bound.
Exempt
Up to$4,035
Up to$5,380
Up to$6,456
Modeled total
$6,095–$7,592
$7,463–$13,748
$12,785–$21,165
$14,590–$24,646
Water & sewer
The City says new detached ADUs "will almost always trigger the requirement for new water and sewer connections and the associated fees". Conversions and attached ADUs usually don't need separate connections but may need a bigger meter. We have not modeled Santa Cruz Water Department or sewer connection charges. 2
Rules
What you can build in Santa Cruz
Maximum size
Non-exempt detached ADU: 10% of net lot area up to 1,200 sq ft, or 850 sq ft (studio or 1 bedroom) / 1,000 sq ft (2+ bedrooms). A Statewide Exemption detached ADU: up to 800 sq ft. 2
Height
Non-exempt detached ADU: up to 22 ft to the roof peak. Statewide Exemption ADU: 16 ft (18 ft near transit). 2
Setbacks
Non-exempt detached ADU: 3 ft from interior side and rear lines; 4 ft for any part over 16 ft tall. Statewide Exemption ADU: 4 ft. 2
Parking
None outside the Coastal Zone. Inside it, one space near the coast (City GIS layer "ADU Parking Required"). 2
State law: every city must run a program to pre-approve ADU plans (Gov. Code 65852.27). Local rule not captured yet.4
Junior ADU (JADU)
Up to 500 sq ft; the owner must live in the JADU or the main home and record a land use agreement. 2
State law
Why a 750 sq ft ADU pays no impact fees
California bars impact fees on ADUs of 750 sq ft or less of interior livable space. Above that, they must be proportional to the main home’s size; we assume 2,000 sq ft unless you enter yours. School fees start at 500 sq ft. From January 1, 2027, SB 1117 limits impact fees to the area over 750 sq ft. How the state rules work →
ADU permits issued
Santa Cruz issued 79 ADU building permits in 2025
626 from 2018 to 2025, as the jurisdiction reported to the state in its Housing Element Annual Progress Reports (Table A2, ADU rows; may include JADUs). “–” means no ADU rows were reported that year.
The Governor approved SB 1117 (Chapter 809, Statutes of 2026) on September 29, 2026. It amends Gov. Code 66311.5: on lots with up to two ADUs, impact fees on an ADU over 750 sq ft must still be proportional to the primary home, and may only be charged on the area over 750 sq ft. Regular 2026 statutes take effect January 1, 2027. Until then, fees on a larger ADU are figured on its full size. Our calculator has a 2027 setting that shows the difference.
The Department of Housing and Community Development updated its ADU Handbook to reflect the laws that took effect January 1, 2026. Its proportional-fee example: a 1,000 sq ft ADU next to a 2,000 sq ft home pays 50% of the fee a new home would pay. Our models use 2,000 sq ft as the example primary-home size unless you enter your own.
On January 28, 2026 the State Allocation Board raised the statewide maximum Level 1 developer fee for residential construction from $5.17 to $5.38 per sq ft (+4.06%). School districts collect it on ADUs of 500 sq ft or more, at their own adopted rate up to this cap (higher Level 2/3 fees need extra findings). Where we haven't confirmed a district's rate, we use $5.38 as the upper bound.
SB 543 (Chapter 520, Statutes of 2025) took effect January 1, 2026. It restates the impact-fee rule in Gov. Code 66311.5: no impact fees on an ADU of 750 sq ft of interior livable space or less, or a JADU of 500 sq ft or less; above that, fees must be proportional to the primary home. It also caps JADUs at 500 sq ft of interior livable space. Many city documents still cite the older section numbers (65852.2 or 66324).
For a detached ADU with a 2,000 sq ft main home (an example assumption), our model of Santa Cruz’s official fee schedules comes to $7,463–$13,748 at 750 sq ft and $12,785–$21,165 at 1,000 sq ft. Ranges show fees that may or may not apply to your project.
Does Santa Cruz charge impact fees on a 750 sq ft ADU?
No. California Government Code section 66311.5 bars impact fees on an ADU of 750 sq ft of interior livable space or less (500 sq ft or less for a JADU). Above 750 sq ft, impact fees must be proportional to the size of the main home. At 1,000 sq ft, the impact fees we model for Santa Cruz come to at most $3,958.
Do school fees apply to an ADU?
Only at 500 sq ft or more. School districts charge their adopted developer fee per sq ft, capped at the State Allocation Board’s Level 1 maximum ($5.38 per sq ft since January 28, 2026) unless they qualify for higher levels.
How big can an ADU be in Santa Cruz?
Non-exempt detached ADU: 10% of net lot area up to 1,200 sq ft, or 850 sq ft (studio or 1 bedroom) / 1,000 sq ft (2+ bedrooms). A Statewide Exemption detached ADU: up to 800 sq ft.
A local agency, special district, or water corporation shall not impose any impact fee upon the development of an accessory dwelling unit that has 750 square feet of interior livable space or less