| Berkeley costs Checked Oct 18, 2026 | Detached ADU No published total; see fee lines or the city's Permit Fee Estimator Source: City of Berkeley · City of Berkeley | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building permit (valuation-based): $150 for the first $3,000 of valuation, plus $2.40 per $100 above that; $62.50 filing fee Fee schedule effective July 1, 2026. The city's Permit Fee Estimator works from valuation. City of Berkeley · City of Berkeley -
Plan check: 65% of the building permit fee Pre-approved ADU plans pay half the regular plan check fee. City of Berkeley · City of Berkeley -
Surcharges on the building permit fee: Access 12%, energy 12%, fire plan check 7%, community planning 6%, green building 6%; technology fee 6.5% City of Berkeley -
Zoning plan check and neighbor notice: $250 + $500 City of Berkeley · City of Berkeley -
Address assignment: $250 City of Berkeley -
City impact fees: $0 Berkeley's Land Use Planning does not charge impact fees on ADUs. City of Berkeley -
School fees (Berkeley Unified): $5.17 per sq ft, ADUs over 500 sq ft City of Berkeley · Berkeley Unified School District · Berkeley Unified School District -
Sewer lateral permit (city): $152 per permit + $247 per month of inspection City of Berkeley -
Water capacity charge (EBMUD): $19,527 per new residential meter 1 inch or smaller EBMUD applies it to ADUs only as state law allows. Conversion ADUs and JADUs are exempt. Other single-family ADUs may pay a proportional charge and may share the main meter. EBMUD · EBMUD -
Wastewater capacity charge (EBMUD): $3,768 per new residential meter 1 inch or smaller Imposed on ADUs only as state law allows. EBMUD · EBMUD |
| Burlingame costs Checked Oct 18, 2026 | Detached ADU (no published total) No published total; see fee lines Source: City of Burlingame | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building permit (valuation-based): ICC valuation x 2.29, then a tiered fee table For example, a $100,001 to $500,000 valuation pays $5,218.30 plus $9.15 per extra $1,000. City of Burlingame -
Plan review and surcharges: Building plan review 65% of the permit fee; planning and engineering review 25% each where they apply; technology fee 2%; general plan maintenance 0.2% of valuation Plan check fees are due when you submit. City of Burlingame -
Development impact fees: $9,391 per single-family unit General $2,825, library $2,443, police $448, parks $605, traffic $1,612, fire $658, storm drain $801. The schedule has no ADU line; state law bars impact fees under 750 sq ft. City of Burlingame · California Department of Housing and Community Development (HCD) -
School fees: San Mateo Union HSD $2.15 per sq ft, plus Burlingame School District Burlingame SD's 2024 study proposed $3.10 per sq ft; we could not confirm the adopted rate. Under state law, ADUs of 500 sq ft or less pay no school fees. San Mateo Union HSD · Burlingame School District · California Department of Housing and Community Development (HCD) -
Sewer capacity charge (City of Burlingame): $5 per sq ft for ADUs over 150 sq ft City of Burlingame -
Water capacity charge (City of Burlingame): $3 per sq ft for ADUs over 150 sq ft A water service connection with sidewalk replacement is $995. City of Burlingame |
| Campbell costs Checked Oct 18, 2026 | Detached ADU No published total; see fee lines Source: City of Campbell | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building permit, by valuation: 2.00% of the first $500,000 of valuation ($237 minimum) Plan check adds 33% of the permit fee. Fire plan check adds $119 or 10%, whichever is greater. FY 2027 schedule, effective July 1, 2026. City of Campbell -
Valuation and size add-ons: General Plan 0.16%, technology 0.04%, training 0.02% and roadway 0.32% of valuation, plus $0.50 per sq ft construction license tax City of Campbell -
Planning plan check: $259 detached; $517 attached; $647 conversion City of Campbell -
Park in-lieu fee: $0 under 750 sq ft; up to $9,328 at 750 sq ft and up; $0 for a JADU Figured under state law and capped at that amount. A new single-family home pays $33,025. City of Campbell -
School fees: $1.61 to $3.79 per sq ft by district Campbell Union SD charges $3.79 and Campbell Union HSD $1.61. Parts of the city may be in Moreland or Cambrian districts instead. Ask your districts before you budget. Campbell Union SD · Campbell Union HSD · Moreland School District · Cambrian School District -
Sewer connection (West Valley Sanitation District): $6,727 max connection + $1,024 max treatment plant capacity Smaller ADUs pay $511.16 and $73.53 per drainage fixture unit. The district's fee tables are labeled FY2018/19 to FY2020/21. West Valley Sanitation District |
| Cupertino costs Checked Oct 18, 2026 | Detached ADU No published total. Plan check and inspection are $4,058 + $4,164 for 500 to 999 sq ft. Source: City of Cupertino | Plan check and inspection are separate fee lines, not a combined city total. School, utility and any applicable park or storm drain charges need a separate check. Fee lines and conditions -
ADU plan check: $2,795 up to 499 sq ft; $4,058 for 500 to 999 sq ft Resolution 26-047, effective July 1, 2026. City of Cupertino -
ADU inspection: $2,975 up to 499 sq ft; $4,164 for 500 to 999 sq ft ADUs of 1,000 sq ft and up have no separate ADU line. City of Cupertino -
Park land in-lieu fee: $0 under 750 sq ft; at 750 sq ft and up, $15,000 or a share scaled to the main home, whichever is less City of Cupertino · City of Cupertino -
Storm drain fee: $0 under 750 sq ft Larger ADUs may pay the per-unit Master Storm Drain Area fee. City of Cupertino · City of Cupertino -
School fees: Cupertino Union SD $3.23 + Fremont Union HSD $2.15 per sq ft The city says ADUs under 750 sq ft pay no school fees. Fremont Union HSD's own sheet exempts 500 sq ft or less. Ask both districts. Cupertino Union SD · Fremont Union HSD · City of Cupertino · Fremont Union HSD -
Water and sewer: Not published by the city The city says to ask your water provider and PG&E whether you need separate meters. City of Cupertino |
| Fremont costs Checked Oct 18, 2026 | Detached ADU No published total; see fee lines Source: City of Fremont · City of Fremont Planning Division | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building plan check and inspection (valuation table): $967.27 for the first $100,000 of valuation, plus $5.91 per extra $1,000 up to $500,000 Minimum valuation for a new wood-frame home (R-3, type VB) is $210.01 per sq ft. Add a $153 application fee, a 15% community planning fee and a 3% technology fee. Trade plan check on new construction is 25% of building plan check, $292 minimum per trade. City of Fremont · City of Fremont -
Ministerial design review (ADU/JADU, new): $2,000 deposit, billed at cost City of Fremont -
Plan review with a preapproved plan: $1,000 flat Construction and inspection fees still apply. City of Fremont -
New address: $278 Every ADU and JADU needs its own address. City of Fremont · City of Fremont Planning Division -
Construction tax: $3,137 per new single-family dwelling unit The schedule has no ADU line. Ask the city whether it applies to your ADU. City of Fremont -
City impact fees: $0 at any size Fremont says ADUs are not subject to its development impact fees, regardless of size. City of Fremont Planning Division · City of Fremont (Code Publishing) -
School fees (Fremont Unified): $5.38 per sq ft over 500 sq ft ADUs of 500 sq ft or less pay nothing. Above that, the whole square footage is charged. Fremont Unified School District -
Sewer capacity charge (Union Sanitary District): $6.46 per sq ft from Oct 1, 2026 Applies to detached ADUs and additions over 150 sq ft; none for an ADU inside existing living space. USD says this is not an impact fee, so the state exemption under 750 sq ft does not apply. It rises each year to $7.18 per sq ft in FY2032. Union Sanitary District · Union Sanitary District -
Water connection (Alameda County Water District): $11,093 per single-family dwelling unit ACWD's schedule has no ADU line. State law says utility charges for an ADU must be in proportion to its size or plumbing fixtures, and an ADU inside existing space pays none. Alameda County Water District · California Department of Housing and Community Development (HCD) |
| Los Altos costs Checked Oct 18, 2026 | Detached ADU (no published total) $0 for the city ADU building permit, trade permits and plan check Source: City of Los Altos | The zero-dollar lines cover the listed ADU permits and plan check only. School fees and any applicable sewer permit, tap-in or other charges are separate. Fee lines and conditions -
ADU building permit, trade permits and plan check: $0 The FY 2026-27 schedule lists the ADU building permit, ADU electrical, mechanical or plumbing permit, and ADU plan check at $0.00. City of Los Altos -
Construction tax: $0.42 per sq ft (single family) The schedule does not say whether ADUs pay it. City of Los Altos -
Impact fees: $0 under 750 sq ft; above that, proportional to unit size We found no city park or impact fee amounts for ADUs. California Department of Housing and Community Development (HCD) · City of Los Altos (Municode, official code host) -
School fees: Los Altos SD $3.58 per sq ft; MVLA high school $1.72 per sq ft Only for ADUs over 500 sq ft. MVLA rises to $1.79 on Nov 13, 2026. Los Altos School District · Mountain View-Los Altos Union HSD · California Department of Housing and Community Development (HCD) -
Water and sewer connection: Not charged as a new residential use (city code) The ADU can share the main home's service or have its own meters. The fee schedule lists a $759.16 city sewer permit and a $152.04 tap-in; ask Public Works which apply. City of Los Altos (Municode, official code host) · City of Los Altos |
| Los Gatos costs Checked Oct 18, 2026 | Detached ADU No published total; see fee lines Source: Town of Los Gatos | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building permit, by valuation: $1,749 for the first $100,000, plus $9.84 per $1,000 up to $500,000 Valuation is the ICC table × 2.32 (× 3.246 on hillside lots). FY 2026-27 schedule, effective July 1, 2026. Town of Los Gatos -
Plan review and surcharges: Plan review 65% and Title 24 surcharge 15% of the building fee; $68 issuance; electrical, mechanical and plumbing $0.12 per sq ft each Town of Los Gatos -
Planning add-ons: Planning plan check 20% of the building fee; General Plan surcharge 0.5% of valuation; 4% permit tracking Town of Los Gatos -
Traffic impact fee: $0 under 750 sq ft; $1,128 per daily trip at 750 sq ft and up, scaled to the main home The Town does not publish the trip rate it uses for an ADU. Town of Los Gatos · Town of Los Gatos -
Construction taxes: $0.18 capital improvement + $0.18 underground utility + $0.04 park fund, per sq ft of added floor area The schedule doesn't say whether these apply to a detached ADU. Town of Los Gatos -
School fees: Los Gatos Union SD $4.07 + Los Gatos-Saratoga Union HSD $1.66 per sq ft LGUSD charges nothing on remodels under 500 sq ft. Campbell Union HSD ($1.61) also lists Los Gatos. Check which districts serve your parcel. Los Gatos Union SD · Los Gatos-Saratoga Union HSD · Campbell Union HSD -
Sewer connection (West Valley Sanitation District): $6,727 max connection + $1,024 max treatment plant capacity Smaller ADUs pay $511.16 and $73.53 per drainage fixture unit. The district's fee tables are labeled FY2018/19 to FY2020/21. West Valley Sanitation District -
Water (San Jose Water): No published ADU fee San Jose Water quotes new service installation costs case by case. San Jose Water |
| Milpitas costs Checked Oct 18, 2026 | ADU, 800 sq ft (city estimate, minimum) $5,255.11 Minimum totals from the city's ADU Permit Fee Estimate (FY 2025-26 fees, dated 6/11/2026). They cover building fees plus minimum planning and land development review, for any new ADU of that size. Not included: school fees over 500 sq ft, utility connections, a possible $703 fire sprinkler review and a $709 new address. At 500 sq ft the estimate is $4,048.31. Source: City of Milpitas Office of Building Safety | Minimum estimate for an 800 sq ft ADU using FY 2025–26 fees. School fees, utility connections, possible fire sprinkler review and a new address are excluded. No combined total under the newer schedule is published. Fee lines and conditions -
Plan review and inspection, scaled by size: 500 sq ft: $1,390.08 + $1,945.85; 1,000 sq ft: $2,265.84 + $2,918.77 Plus a 3.8% permitting automation fee, a 5% community planning fee and state fees. Schedule effective Aug 3, 2026. City of Milpitas Office of Building Safety -
Planning and land development review: Planning $275 an hour (half-hour minimum); land development $231 an hour (1-hour minimum) City of Milpitas Office of Building Safety -
No-fee ADU permits: The city covers permit fees for eligible ADUs, about $5,000 on average A limited-time program. The city's notice is undated, so ask adu@milpitas.gov if it is still open. City of Milpitas -
Park and impact fees: No park fee for ADUs; no impact fees under 750 sq ft ADUs of 750 sq ft or more pay other impact fees in proportion to the main home. City of Milpitas Office of Building Safety · City of Milpitas -
School fees (Milpitas Unified): $5.17 per sq ft on the whole ADU at 500 sq ft and up Milpitas Unified School District -
Water connection (City of Milpitas): $1,910 × (ADU sq ft ÷ main home sq ft) Only when a new connection is needed or requested. City of Milpitas Office of Building Safety -
Sewer and treatment plant connection (City of Milpitas): $1,908 sewer + $880 treatment plant, each × (ADU sq ft ÷ main home sq ft) Only when a new connection is needed or requested. City of Milpitas Office of Building Safety -
Fire sprinkler review and new address: $703 sprinkler review if it applies; $709 new address request City of Milpitas Office of Building Safety |
| Mountain View costs Checked Oct 18, 2026 | New detached ADU, building permit (city's typical range) $7,000 to $13,000 in building permit fees, including inspections Source: City of Mountain View | Building permit range, including inspections. School fees are separate. Planning, impact and utility charges need a parcel-specific check. Fee lines and conditions -
Building permit, new ADU (city's typical range): $7,000 to $13,000 Based on a construction valuation of $100,000 to $300,000; includes inspections. Conversions run $3,000 to $5,000 and a JADU $4,000 to $6,000. City of Mountain View -
Excavation permit, if you need utility or sidewalk work: Up to $12,000 City of Mountain View -
Land use document fee: 0.24% of construction valuation Collected on all projects at building permit. City of Mountain View -
Citywide transportation fee: $6,273.15 per new single-family unit The city's page has no ADU line. State law: no impact fees under 750 sq ft; above that, a share in proportion to the main home. City of Mountain View · California Department of Housing and Community Development (HCD) -
Park land in-lieu fee: Based on land value: $160 to $210 per sq ft of land at low density The page does not say how this applies to ADUs. State law bars it under 750 sq ft. City of Mountain View · California Department of Housing and Community Development (HCD) -
School fees: Mountain View Whisman $3.45, Los Altos SD $3.58, MVLA high school $1.72 per sq ft For 500 sq ft or more. You pay the districts directly and show the receipt before the permit is issued. MVLA rises to $1.79 on Nov 13, 2026. City of Mountain View · City of Mountain View · Mountain View Whisman SD · Los Altos School District · Mountain View-Los Altos Union HSD -
Water capacity fee (City of Mountain View): $9,389.06 per single-family detached unit No ADU line. State law limits capacity charges to a share based on the ADU's size or plumbing fixtures. Conversions that fix a code or zoning problem pay none unless new utility work is needed. City of Mountain View · California Department of Housing and Community Development (HCD) · City of Mountain View -
Sewer capacity fee (City of Mountain View): $7,922.69 per single-family detached unit No ADU line. The same state proportionality rule applies. City of Mountain View · California Department of Housing and Community Development (HCD) |
| Oakland costs Checked Oct 18, 2026 | Detached ADU No published total; see fee lines Source: City of Oakland | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building plan review and inspection, new construction (R-3): $10.60 plan review + $8.00 inspection per $1,000 of valuation Add the 12.70% records and technology fee and the 7.20% General Plan surcharge. FY 2026-27 schedule, effective July 1, 2026. City of Oakland -
Zoning review (Report Fee for ADU, Category I, II or III): $878.58 per application City of Oakland -
City impact fees: $0 ADUs are exempt from Oakland's affordable housing, transportation and capital improvements impact fees. City of Oakland -
School fees (Oakland Unified): $5.17 per sq ft Collected by the city for OUSD. The city page does not say how ADUs are charged. State law lets districts charge only ADUs over 500 sq ft. City of Oakland · California Department of Housing and Community Development (HCD) -
New sewer lateral connection (city): $1,798.93, up to 3 inspections Detached ADUs need a sewer lateral permit. If your valuation is over $100,000 you also need an EBMUD Private Sewer Lateral certificate. City of Oakland · City of Oakland -
Water capacity charge (EBMUD): $19,527 per new residential meter 1 inch or smaller EBMUD applies it to ADUs only as state law allows. Conversion ADUs and JADUs are exempt. Other single-family ADUs may pay a proportional charge and may share the main meter. EBMUD · EBMUD -
Wastewater capacity charge (EBMUD): $3,768 per new residential meter 1 inch or smaller Imposed on ADUs only as state law allows. EBMUD · EBMUD -
ADU amnesty application: $1,461.53 City of Oakland |
| Palo Alto costs Checked Oct 18, 2026 | Detached ADU building permit (flat fee) $7,346 Source: City of Palo Alto | Building permit only. School and utility capacity charges are separate. The schedule does not say whether plan check percentages are added to this flat fee. Fee lines and conditions -
Detached ADU building permit: $7,346 per permit; $2,653 for a master-plan permit Site-specific permits tied to a master plan: $3,929 for prefab, $5,481 for site-built. City of Palo Alto -
Plan checks: Building plan check 125% of the permit fee; planning and public works plan checks 35% each The schedule does not say whether these apply on top of the flat ADU fee. City of Palo Alto -
City guidebook ranges: $2,000 to $8,000 in building permit fees; $10,000 to $80,000 in impact fees Impact fees apply only at 750 sq ft and up. City of Palo Alto -
Development impact fees (parks, community center, library, public safety, general government): $0 under 750 sq ft. At 750 sq ft and up, a share of the single-family rates: parks $18.75, community center $1.44, libraries $0.86 per sq ft; public safety $1,383 and general government $1,743 per unit The share is in proportion to the size of the main home. JADUs and garage conversions with no added floor area are exempt. City of Palo Alto · City of Palo Alto -
School fees: Palo Alto Unified $4.79 per sq ft; Los Altos SD $3.58 per sq ft Only for ADUs over 500 sq ft. You pay the district directly; the city does not collect it. City of Palo Alto · Palo Alto Unified School District · Los Altos School District · City of Palo Alto -
Water capacity charge (City of Palo Alto Utilities): $3,750 for a 5/8 x 3/4-inch meter; $6,250 for a 1-inch meter Charged when CPAU requires a new service. A JADU is not a separate unit for water, sewer or power. City of Palo Alto · City of Palo Alto (American Legal Publishing, official code host) -
Wastewater capacity charge (City of Palo Alto Utilities): $5,250 for a 4-inch connection with a 5/8-inch meter; $10,500 with a 1-inch meter City of Palo Alto |
| Redwood City costs Checked Oct 18, 2026 | Base permit fee, new ADU 601 to 800 sq ft $5,321.71 Source: City of Redwood City · City of Redwood City | Base permit only. Valuation-based fees may be added. School and water charges are separate; see the city breakdown for exemptions and other charges. Fee lines and conditions -
Base permit fee, new ADU: $3,999.53 up to 400 sq ft or a garage conversion; $4,660.62 for 401 to 600 sq ft; $5,321.71 for 601 to 800 sq ft Valuation-based fees are added case by case. City of Redwood City · City of Redwood City -
Transportation, park and housing impact fees: $0 for ADUs A council resolution exempts ADUs from these three fees until April 1, 2027. The ADU page also says no impact fees under 750 sq ft. City of Redwood City · City of Redwood City · City of Redwood City · City of Redwood City -
School fees: $5.17 per sq ft, split between Sequoia Union HSD and your elementary district For 500 sq ft or more of living space. You write two checks. City of Redwood City · Sequoia Union HSD · Sequoia Union HSD -
Wastewater collection capacity fee (City of Redwood City): $1.78 per sq ft The wastewater treatment capacity fee does not apply to ADUs. City of Redwood City -
Water capacity fee (City of Redwood City): $3.19 per sq ft The city says water and sewer capacity fees apply to ADUs. City of Redwood City · City of Redwood City -
Address for the ADU: $376 City of Redwood City |
| San Francisco costs Checked Oct 18, 2026 | New ADU No published total. sf.gov says City fees run 6% to 9% of construction cost. Source: City & County of San Francisco (sf.gov / DBI) | The percentage is a city rule of thumb, not a quote or a published dollar total. Check the fee lines and any meter installation costs for your project. Fee lines and conditions -
City fees, all departments (sf.gov rule of thumb): 6% to 9% of construction cost sf.gov says a new unit typically costs at least $125,000 in material and labor, and architects and engineers add about 10%. City & County of San Francisco (sf.gov / DBI) -
Building permit, DBI Table 1A-A (valuation $200,001 to $500,000): Plan review $4,011 + $13.31 per extra $1,000; issuance $1,402 + $4.21 per extra $1,000 For permits issued on or after July 12, 2026. Other departments' fees and trade permits are extra. SF DBI -
Permit Review Roundtable (State program): $0 extra sf.gov -
Impact fees: $0 under 750 sq ft or on lots with 3 or fewer units; otherwise in proportion to the main home Planning Code Article 4 impact fees were cut 67% from Aug 22, 2026. The inclusionary fee was not cut. SF Planning · SF Planning -
School fees (SF Unified): $3.79 per sq ft DBI calculates the fee from your application. The city register does not say how ADUs are charged; state law lets districts charge only ADUs over 500 sq ft. SF Planning · City & County of San Francisco (sf.gov / DBI) · California Department of Housing and Community Development (HCD) -
Water and sewer capacity charges (SFPUC): $0 for an ADU on a single-family lot SFPUC won't make you upsize your meter. If you choose a new or bigger meter, you pay installation fees only. Buildings with more units pay capacity charges when they add ADUs. SFPUC · SFPUC |
| San Jose costs Checked Oct 18, 2026 | Detached ADU up to 750 sq ft $13,092 Averages of ADU permits San José issued in the last 12 months, from the city's Building Fee Estimator. Not a quote. School fees are not included. Source: City of San José · City of San José Building Fee Estimator (New ADU results) | Historical average of issued permits, including permit issuance, plan check, trade permits and taxes. School fees are excluded. Check water service and other parcel-specific charges separately. Fee lines and conditions -
Building permit, plan review and inspection (fee schedule): $3,323 up to 750 sq ft; $5,151 for 751 to 1,200 sq ft Modular units pay 10% less for plan review and 20% less for inspection. City of San José Building Division -
Construction taxes: 3.96% of valuation, plus $330 per unit Valuation uses $169.09 per sq ft. City of San José Building Division -
Parkland fee: $0 under 750 sq ft; $1,700 to $8,900 at 750 sq ft and up, by zone City of San José · City of San José -
School fees: $1.36 to $5.38 per sq ft, set by your school districts San José says ADUs under 750 sq ft pay none. East Side Union HSD says they do, and most districts only exempt 500 sq ft or less. Ask both of your districts before you budget. City of San José · East Side Union HSD · CA DGS / Office of Public School Construction (State Allocation Board) -
Sewer, storm drain and treatment plant: $447 sewer + $270 storm drain per lot; treatment plant $780 per unit The schedule has no ADU-specific line; confirm at the counter whether these apply to your ADU. City of San José Building Division -
Water service: Depends on your water company San Jose Water, Great Oaks Water, or San José Municipal Water. Separate meters are optional. City of San José · City of San José |
| San Mateo costs Checked Oct 18, 2026 | New ADU building permit (flat fee) $2,831.57 Source: City of San Mateo | Building permit only. School fees and wastewater capacity charges are separate. Whether valuation add-ons apply is unclear; water connection costs are not recorded. This is not the total city fee. Fee lines and conditions -
ADU building permit (flat fee): $2,831.57 new ADU; $1,455.43 manufactured, prefab or pre-approved; $1,454.02 JADU ADU remodel: $2,031.12. City of San Mateo -
Valuation-based add-ons: General plan maintenance 0.59%, technology 0.15%, park and rec tax $0.30 per $100 of valuation The schedule does not say whether these apply on top of the flat ADU fee. City of San Mateo -
Transportation and child care fees: $7,339.55 transportation and $4,677.29 child care per single-family unit The schedule has no ADU line. State law: no impact fees under 750 sq ft; above that, a share in proportion to the main home. City of San Mateo · California Department of Housing and Community Development (HCD) -
School fees: $5.02 per sq ft (San Mateo-Foster City SD and San Mateo Union HSD combined) San Mateo Union HSD collects it. Under state law, ADUs of 500 sq ft or less pay no school fees. San Mateo Union HSD · California Department of Housing and Community Development (HCD) -
Wastewater capacity charge (City of San Mateo): $5.87 per sq ft of ADU At that rate a 750 sq ft ADU pays $4,402.50. Detached ADUs may need a new connection; JADUs don't. City of San Mateo · City of San Mateo |
| Santa Clara costs Checked Oct 18, 2026 | Detached ADU No published total; see fee lines Source: City of Santa Clara | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building plan review, scaled by size: $732 for the first 250 sq ft, plus $292.80 per 100 sq ft up to 1,000 sq ft; $2,928 at 1,000 sq ft, plus $146.40 per 100 sq ft above that A 3.37% technology fee is added. City of Santa Clara -
Building permit fee, scaled by size: $812 for the first 250 sq ft, plus $249.50 per 100 sq ft up to 1,000 sq ft; $2,684 at 1,000 sq ft, plus $211.40 per 100 sq ft above that A 3.37% technology fee is added. City of Santa Clara -
Architectural Review for an ADU or JADU: $306 Only if your ADU doesn't qualify for the building-permit-only path. City of Santa Clara · City of Santa Clara Planning Division -
Park fee: $0 under 750 sq ft The fee schedule has no ADU park line. State law bars impact fees under 750 sq ft; larger ADUs pay in proportion to the main home. City of Santa Clara · California Department of Housing and Community Development (HCD) -
School fees: Santa Clara Unified: $5.38 per sq ft; $0 under 500 sq ft Santa Clara Unified School District -
Sewer conveyance fee (City of Santa Clara): $1.14 per sq ft for ADUs 750 sq ft and larger; $0 under 750 sq ft City of Santa Clara -
Wastewater treatment plant capacity fee (City of Santa Clara): $747 per ADU City of Santa Clara -
Water service (City of Santa Clara): No ADU line; a new 1-inch meter is $239 for the device Only if you add a meter. Ask Water & Sewer Utilities what your ADU needs. City of Santa Clara |
| Saratoga costs Checked Oct 18, 2026 | Detached ADU No published total; see fee lines Source: City of Saratoga | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building permit, by valuation: $1,693 for the first $100,000, plus $9.60 per $1,000 up to $500,000 Valuation is the ICC table × 2.9. Fee schedule effective July 1, 2026. City of Saratoga -
Plan check and surcharges: Plan check 66% of the permit fee; 8.10% technology surcharge; General Plan fee 0.285% of valuation; $170 address processing City of Saratoga -
Park development fee: $0 up to 750 sq ft; above that, a share of $56,845 scaled to the main home The city's 2024 handout says ADUs under 700 sq ft are exempt; the newer web page says 750. City of Saratoga · City of Saratoga · City of Saratoga -
Below-market rent fee waiver: All planning, building and engineering fees waived Only for an ADU or JADU deed-restricted to below-market renters. City of Saratoga -
School fees: Saratoga Union SD $0.70 + Los Gatos-Saratoga Union HSD $1.66 per sq ft Saratoga Union SD charges nothing under 500 sq ft. Campbell Union HSD also lists Saratoga, and Cupertino Union, Fremont Union HSD and Moreland may serve some parcels. Check yours. Saratoga Union SD · Los Gatos-Saratoga Union HSD · Campbell Union HSD -
Sewer connection (West Valley Sanitation District): $6,727 max connection + $1,024 max treatment plant capacity The city lists West Valley Sanitation as the sewer contact. Smaller ADUs pay $511.16 and $73.53 per drainage fixture unit. City of Saratoga · West Valley Sanitation District -
Water: No published ADU fee The city says some ADUs need a new water or sewer connection. San Jose Water quotes new service costs case by case. City of Saratoga · San Jose Water |
| Sunnyvale costs Checked Oct 18, 2026 | Detached ADU No published total; see fee lines. The city's ADU Calculator gives rough estimates. Source: City of Sunnyvale · City of Sunnyvale | No combined fee total is published. Permit and review fees, school fees and utility charges are listed separately; confirm which apply to your lot. Fee lines and conditions -
Building permit, by valuation: $2,445 for the first $100,000 of valuation, plus $13.50 per $1,000 up to $500,000 The Building Division sets valuation from its own tables. FY 2026/27 fees, effective Aug 18, 2026. City of Sunnyvale -
Plan check, energy and fire: Plan check 70%, energy plan check 10% and fire permit 70% of the building permit fee City of Sunnyvale -
Issuance and trade permits: $42.50 issuance; 5% technology surcharge; electrical, mechanical and plumbing $0.15 per sq ft each ($130 minimum) City of Sunnyvale -
Construction tax and General Plan fee: 0.54% plus 0.15% of valuation City of Sunnyvale -
Transportation impact fee: $0 at 750 sq ft and under; larger ADUs pay a share of $5,095 per single-family home Rate for south of Route 237. The ADU's share is set in proportion to the main home. City of Sunnyvale · City of Sunnyvale · GoCodebook (third-party mirror) -
Park in-lieu fee: $0 under 750 sq ft The impact fee sheet has no ADU line. State law bars impact fees under 750 sq ft. City of Sunnyvale · California Department of Housing and Community Development (HCD) -
School fees: New ADUs 500 sq ft and up; $1.72 to $5.38 per sq ft by district Sunnyvale SD charges $3.32 and Fremont Union HSD $2.06 in its Sunnyvale area. You pay both your elementary and high school district, directly to them, before the permit is issued. City of Sunnyvale · City of Sunnyvale · Sunnyvale School District · Fremont Union HSD · Mountain View-Los Altos Union HSD · Santa Clara Unified School District -
Sewer and water connection (City of Sunnyvale): $0; incremental connection fees are exempt for single-family ADUs Once the ADU is finaled, your lot is billed at two-unit multifamily utility rates. More than 5 toilets on site means a 4-inch sewer line. City of Sunnyvale |