San José allows one ADU plus one JADU on any lot with a legally permitted single-family home, and ADUs on duplex and multifamily lots, under San José Municipal Code 20.80.175 (Chapter 20.80, Part 2.75). You choose one of two standards tracks: City standards (SJMC 20.80.175) allow a 1,000 sq ft ADU on lots up to 9,000 sq ft and 1,200 sq ft on larger lots with 0 ft first-story side and rear setbacks and 18-25 ft heights; State standards (SJMC 20.80.176, Gov. Code 66323) allow 800 sq ft with 4 ft setbacks and a 16 ft height. The permit is a ministerial building permit filed on SJPermits.org and reviewed in SJePlans; the FY 2026-27 fee schedule (effective Aug 10, 2026) sets city permit fees at $3,291 for an ADU of 0-750 sq ft and $5,103 for 751-1,200 sq ft, and the first review round typically takes 20 business days. No parking, no owner-occupancy for an ADU, and no school or parkland impact fees for a unit of 750 sq ft or less. The last ADU amendment, Ordinance No. 31329 (adopted June 16, 2026, effective July 16, 2026), moved JADU rules to Gov. Code 66333.
Zoning & Size Requirements [1][2][3][4][5]
Yes — San Jose allows ADUs. A detached ADU can typically be up to 1,000 sq ft under current California and San Jose zoning rules.
See what this means for your lot — ask San Jose ADU builders for a quote →
| Allowed Zones | Any zoning district where the lot has a legally permitted single-family, duplex or multifamily dwelling (SJMC 20.80.175 A; ADU Universal Checklist, Bulletin #210 rev. Sept 16, 2026, Part 1). An open Code Enforcement case must be closed before plans are accepted. Flood zones A/AE/AH/AO, geohazard, landslide or liquefaction zones, Historic Resources Inventory listing and Wildland-Urban Interface areas add design rules or clearances rather than prohibiting the unit. |
| Max Size (Detached) | Two tracks that cannot be mixed. City standards (SJMC 20.80.175 D.1, Table 20-55): 1,000 sq ft on lots up to 9,000 sq ft, 1,200 sq ft on larger lots, and no cap when converting an existing detached accessory structure. State standards (SJMC 20.80.176 / Gov. Code 66323): 800 sq ft. Minimum 150 sq ft on either track. Square footage is livable floor space measured to the exterior finish; a covered porch or balcony more than 50% enclosed counts (20.80.175 E.3). |
| Max Size (Attached) | City standards: up to 50% of the existing primary dwelling's living area, capped at 1,000 sq ft on lots up to 9,000 sq ft and 1,200 sq ft on larger lots (SJMC 20.80.175 D.1). State standards: 800 sq ft, and no attached ADU where a conversion ADU exists or is proposed (Bulletin #210 Part 3, note 5). Minimum 150 sq ft. The unit must share a common wall or integral roof with the main home, and its front door may not be on the same street-facing facade (20.80.175 D.5.a, E.2). |
| Max Size (JADU) | 500 sq ft maximum, 150 sq ft minimum, inside the walls of an existing or proposed single-family home (an attached garage counts). Since Ordinance 31329 (effective July 16, 2026) SJMC 20.80.178 applies Gov. Code 66333 directly: an efficiency kitchen is required, the bathroom may be shared, rentals must be 30 days or longer, and a deed restriction (Form 313, wet-signed for the County Recorder) is recorded. One JADU plus one ADU is allowed per single-family lot (20.80.175 B.1). |
| Max Height | City standards (SJMC 20.80.175 D.2): detached one-story 18 ft; detached two-story 25 ft to the roof; attached 25 ft; two stories maximum; 25 ft on duplex/multifamily lots. State standards (Gov. Code 66321(b)(4); Bulletin #210): detached 16 ft, plus 2 ft for a pitched roof within a half-mile walk of a major transit stop or high-quality transit corridor; attached 25 ft; detached on a multifamily lot 18 ft plus 2 ft roof pitch. Roof height is measured per SJMC 20.200.510. |
| Max Units | Single-family lot: 1 ADU (attached or detached) plus 1 JADU (SJMC 20.80.175 B.1). Duplex or multifamily lot under City standards: 1 ADU (B.2). Under State standards (SJMC 20.80.176 / Gov. Code 66323(a)(3)-(4)): up to 8 detached ADUs on a lot with an existing multifamily building (never more than the existing units), up to 2 detached on a lot with a proposed one, plus conversion ADUs of at least 1 and up to 25% of existing units (city example: 5 in a 20-unit building). |
Setback Requirements [1][2][3][4][5]
San Jose allows a 0 ft rear setback for a detached ADU in some cases (the setbacks row gives the conditions), and no additional parking is required. Owner-occupancy is not required — you can rent it out without living on the property.
| Rear Setback | City standards: 0 ft for a one-story detached ADU; 4 ft, with eaves of 1 ft or less, for any second story (SJMC 20.80.175 D.3). State standards: 4 ft. A structure converted to an ADU keeps its existing setback; Building and Fire Code separations and easements still apply. City-track detached units must sit at least 6 ft from the main home and, with other accessory structures, cover no more than 40% of the rear yard, a cap that cannot block an 800 sq ft ADU with 4 ft setbacks (D.5.c, D.5.e). |
| Side Setback | City standards: 0 ft for the first story, 4 ft for a second story (SJMC 20.80.175 D.3.b and D.3.e; Bulletin #210 note 2 confirms zero is allowed subject to Building and Fire Code). State standards: 4 ft on both sides. Conversions keep their existing setbacks. Duplex and multifamily lots use the same figures. A new City-track detached ADU that keeps a 4 ft interior side setback may sit as close as 45 ft to the front property line (D.5.b). |
| Front Setback | The front setback of the zoning district (Title 20 Table 20-60, varies by district) under both tracks, except that it may be encroached if it would otherwise prevent an 800 sq ft ADU (SJMC 20.80.175 D.3.a; Bulletin #210 note 7). City-track detached ADUs must be in the rear yard or, with a 4 ft interior side setback, at least 45 ft back from the front property line (D.5.b); on Historic Resources Inventory lots the 45 ft rule always applies (E.1.c). State-track conversions: no front-setback rule. |
| Parking Required | None. SJMC 20.80.175 I requires no off-street parking for an ADU and no replacement of covered parking removed to build it; Bulletin #210 (rev. Sept 16, 2026) lists parking as 'None' under both the City and the State standards for single-family, duplex and multifamily lots. |
| Owner Occupancy | Not required for an ADU: the owner signs Form 312 (a declaration, not an occupancy covenant) and SJMC 20.80.175 F says a later sale or rental does not affect the unit's legal status. For a JADU, owner-occupancy of the main home is required only if the JADU shares sanitation facilities with it (Gov. Code 66333(b), as amended by AB 1154 and applied by SJMC 20.80.178 since July 2026); a JADU with its own bathroom has none. A Form 313 deed restriction is recorded for every JADU. |
| Min Lot Size | No minimum lot size (the former 3,000 sq ft minimum was removed on December 17, 2019). Lot size only sets the City-track size cap (9,000 sq ft threshold, SJMC 20.80.175 D.1) and, on lots of half an acre or more, a 100 ft setback from any riparian corridor (D.5.f). The minimum ADU size is 150 sq ft (Bulletin #210). |
Permit Process & Fees [6][7][8][9][10][11][12]
An ADU permit in San Jose goes through a ministerial, by-right review. Typical timeline: City-published: the first round of building review typically takes 20 business days and complete plans stay within one or two cycles (ADU FAQs); preapproved plans can be issued the same day as the review meeting. Gov. Code 66317 (SB 543) deems the application approved after 60 days. Permit fees: FY 2026-27 Building Fee Schedule (effective Aug 10, 2026): ADU 0-750 sq ft $422 issuance + $1,137 plan review + $1,732 inspection = $3,291; 751-1,200 sq ft $633 + $1,950 + $2,520 = $5,103. Excludes construction taxes, school and parkland fees and any planner meeting ($398/hour).
| Approval Process | Ministerial building permit, no planning hearing. Step 1: complete the ADU Universal Checklist (Bulletin #210) and, optionally, book a preliminary virtual meeting with a planner ($398/hour, 30-minute minimum). Step 2: prepare plans to Bulletin #211. Step 3: open the application on SJPermits.org (folder '1 & 2 Family Detached Dwellings (including ADU)', sub-type 'ADU') and name an ePlan Applicant. Step 4: upload to SJePlans the plans, Bulletin #213 inspection checklist, Title 24 energy and CALGreen documents, Form 302 address request, Form 312 owner declaration (Form 313 deed restriction for a JADU), and the water company's hydrant flow letter. Step 5: Prescreen, Plan Review and Issuance Review in SJePlans. Step 6: construction, inspections and final. Multifamily lots and AB 2533 legalizations go through the ADU Ally team (adu.ally@sanjoseca.gov); preapproved plans use a separate expedited path. |
| Review Timeline | City-published: the first round of building review typically takes 20 business days and complete plans stay within one or two cycles (ADU FAQs); preapproved plans can be issued the same day as the review meeting. Gov. Code 66317 (SB 543) deems the application approved after 60 days. |
| Permit Fees | FY 2026-27 Building Fee Schedule (effective Aug 10, 2026): ADU 0-750 sq ft $422 issuance + $1,137 plan review + $1,732 inspection = $3,291; 751-1,200 sq ft $633 + $1,950 + $2,520 = $5,103. Excludes construction taxes, school and parkland fees and any planner meeting ($398/hour). |
| Impact Fees | School and parkland impact fees do not apply to an ADU of 750 sq ft or less; at 751 sq ft and larger both apply (Bulletin #210 rev. Sept 16, 2026, item 17, matching Gov. Code 66311.5(c)). Parkland fees vary by location (city Park Impact Fee map); school fees are set and collected by the school district(s) and the city issues a school-fee referral form at submittal. The permit is not issued until both are paid. The fee schedule also lists city development taxes collected at issuance (residential 2.42% plus 1.54% of building valuation, SJMC Chapters 4.46 and 4.47); confirm with the Building Division whether they apply to your ADU. |
| Plan Check | Electronic review in SJePlans in three phases: Prescreen (a permit specialist confirms the package is complete and invoices the initial plan review fee), Plan Review (comment and resubmittal cycles, all through SJePlans), and Issuance Review (residual plan review and inspection fees, taxes, school and parkland fees paid, then the permit card and stamped plans are released). Fire Prevention checks a 150 ft hose path along a 4 ft clear route, a hydrant within 600 ft and a 1,000 gpm at 20 psi flow letter from the water company; the missing letter is the city's most-cited cause of delay. |
| Pre-Approved Plans | Yes. The Preapproved ADU program currently lists 7 city-reviewed standard plans from 5 vendors, 476-799 sq ft (1 bed/1 bath to 2 bed/2 bath); about 15 further plans from 7 vendors, 440-1,000 sq ft, are under review and not yet eligible. Applicants still submit a site-specific plan (siting, setbacks, utilities); a dedicated review team can issue the permit the same day as the plan review meeting when the site documents are complete (deferred structural submittals, clearances or variances take longer). Eligibility: a residential lot with an existing single-family home or duplex, outside geohazard, landslide, flood and Wildland-Urban Interface zones. Gov. Code 65852.27 governs pre-approved plan programs. |
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Construction Costs [13][14][15]
Building an ADU in San Jose typically costs $200,000-$450,000 ($300-$500 per sq ft); a garage conversion runs $90,000-$150,000.
See what this means for your lot — ask San Jose ADU builders for a quote →
| Average Build Cost | $200,000-$450,000 |
| Cost per Sq Ft | $300-$500 |
| Garage Conversion | $90,000-$150,000 |
| Prefab ADU (Installed) | $150,000-$300,000 |
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Rental Income Potential [16][17][18]
A 2-bedroom ADU in San Jose rents for around $3,100-$3,600/mo, an estimated 8-12% gross annual yield on a new build ($3,300/mo on a $350,000 detached unit is about 11% before vacancy, tax and financing); a $120,000 garage conversion at $2,600/mo is nearer 25% gross.
| Avg Rent (1 Bedroom) | $2,500-$3,000/mo |
| Avg Rent (2 Bedroom) | $3,100-$3,600/mo |
| Short-Term Rental | No for stays under 30 days: the city's ADU FAQs set a 30-day minimum rental term for an ADU (including Airbnb-type rentals) and Gov. Code 66333 bars short-term rental of a JADU. Longer rentals to anyone are allowed. |
| Est. Annual ROI | 8-12% gross annual yield on a new build ($3,300/mo on a $350,000 detached unit is about 11% before vacancy, tax and financing); a $120,000 garage conversion at $2,600/mo is nearer 25% gross. |
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Recent Law Changes
What's Changed Recently
- Ordinance No. 31329 (passed June 2, adopted June 16, 2026, effective July 16, 2026): SJMC 20.80.178 now applies Gov. Code 66333 directly to JADUs - owner-occupancy only when the JADU shares a bathroom with the main home (AB 1154) and a 30-day minimum rental term (SB 543); 20.80.185 ADU-condominium clean-up for Department of Real Estate rules.
- Ordinance No. 31298 (adopted Feb 3, 2026): rewrote SJMC 20.80.176 so the State track is Gov. Code 66323 as amended (SB 1211 multifamily allowances), added 20.80.177 (ordinance-size trees removed for an ADU are processed with the ADU approval, 1:1 replacement) and removed the four-unit cap on AB 1033 ADU condominiums in 20.80.185.
- ADU Universal Checklist (Bulletin #210) revised Sept 16, 2026: the impact-fee threshold now reads '750 sq ft or less: no impact fees; 751 sq ft or larger: school and parkland fees apply', matching Gov. Code 66311.5; the multifamily conversion example is now 5 ADUs in a 20-unit building.
- FY 2026-27 Building Division fee schedule effective Aug 10, 2026: ADU permit fees total $3,291 (0-750 sq ft) or $5,103 (751-1,200 sq ft); Planning hourly rate $398.
- SB 543 (effective Jan 1, 2026): ADU applications are deemed approved if the city does not act within 60 days (Gov. Code 66317); AB 1154: JADU owner-occupancy may be required only where the JADU shares a bathroom with the primary dwelling.
- AB 2533 legalization program (city page live 2026): unpermitted ADUs or JADUs built before Jan 1, 2020 can be legalized through the ADU Ally team using the Bulletin #214 substandard-housing checklist; the city says 4 to 6 months from a complete application.
- AB 1033 ADU condominiums: San José has opted in (SJMC Part 2.76, 20.80.181-20.80.185) - an ADU may be sold separately after a parcel map, CC&Rs, an owners' association and each lienholder's written consent.
Tips for Building an ADU in San Jose
- Choose your track before you design. City standards (SJMC 20.80.175) give more size (1,000 or 1,200 sq ft) and 0 ft first-story setbacks but add siting rules: rear yard or 45 ft back, 6 ft from the house, 40% rear-yard cap and historic-property design standards. State standards (20.80.176) give 800 sq ft, 4 ft setbacks and 16 ft with none of those extras. The two cannot be mixed.
- Request the hydrant flow letter from your water company (San Jose Water, Great Oaks Water or San José Municipal Water) on day one with 'ADU Water Flow Request' in the subject line; the city calls the missing letter the most common cause of permit delay.
- Keep the unit at 750 sq ft or less to avoid school and parkland impact fees and stay in the lower permit-fee bracket ($3,291 instead of $5,103); five of the seven preapproved plans are 747-799 sq ft, so check the exact figure.
- Fire sprinklers are required in the ADU if the main house is sprinklered, and an attached ADU over 500 sq ft that pushes the combined floor area past 3,600 sq ft triggers sprinklers for the whole house (Bulletin #210 items 14-15).
- PG&E now requires a separate electric meter for an ADU (not for a JADU), so price the service upgrade early. The city has paused enforcement of its natural-gas ban, so gas or all-electric designs are both accepted.
- Removing an ordinance-size tree (38 in circumference at 4.5 ft) for the ADU needs no separate tree permit but requires 1:1 replacement (4:1 on multifamily lots) under SJMC 20.80.177; heritage trees and Palm Haven palms still need a tree permit.
- Cost basis (Sept 20, 2026): Custom Home San José guide (Feb 19, 2026, updated Apr 21, 2026): garage conversion $120,000-$150,000, attached $150,000-$300,000, detached $250,000-$450,000+, $300-$500 per sq ft; Steadily (updated Aug 10, 2026): detached $150,000-$350,000, garage or JADU $80,000-$150,000; ADUscale (June 2026): prefab $120,000-$250,000, up to $300,000 with site work, Bay Area +25-50%. Rents: HUD FY2027 Small Area FMRs for San José ZIPs 1BR $2,040-$3,790 and 2BR $2,400-$4,460 (most ZIPs $2,460-$3,150 and $2,900-$3,600); Zumper Sept 20, 2026 medians 1BR $2,780, 2BR $3,600; RentCafe Aug 31, 2026 averages 1BR $3,009, 2BR $3,614.
ADU Builders in San Jose
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Sources & References
All data on this page is sourced from official government records and verified market data. View our full methodology.
- San José Municipal Code Title 20, Chapter 20.80, Part 2.75 Accessory Dwelling Units (20.80.175-20.80.179) and Part 2.76 ADU Condominium (20.80.181-20.80.185), codified through Ord. 31330 (June 16, 2026) Municipal Code — Accessed 2026-09-20
- Bulletin #210 ADU Universal Checklist (updated 09/16/2026), City of San José Building Division Planning Department — Accessed 2026-09-20
- Accessory Dwelling Units (ADUs) | City of San José Planning Department — Accessed 2026-09-20
- California Government Code 66321 (size and height floors) and 66323 (streamlined units), as amended by SB 543 effective Jan 1, 2026 State Law — Accessed 2026-09-20
- California Government Code 66333 (junior accessory dwelling units, AB 1154 owner-occupancy rule) State Law — Accessed 2026-09-20
- ADU Project Process (plan review and permit steps) | City of San José Planning Department — Accessed 2026-09-20
- ADU FAQs (fees, review times, rentals, fire questions) | City of San José Planning Department — Accessed 2026-09-20
- Preapproved ADUs | City of San José Planning Department — Accessed 2026-09-20
- FY 2026-27 Building and Structure Permits Fee Schedule, effective August 10, 2026 (p. 3 ADU table; p. 23 development taxes) fee_schedule — Accessed 2026-09-20
- ADU Service (submittal checklist) | City of San José Planning Department — Accessed 2026-09-20
- AB 2533 ADU and JADU Legalization Program | City of San José Planning Department — Accessed 2026-09-20
- California Government Code 66311.5 (impact fees: 750 sq ft of interior livable space or less exempt) and 66317 (60-day deemed approval) State Law — Accessed 2026-09-20
- ADU Construction Costs in San Jose 2026 (published Feb 19, 2026, updated Apr 21, 2026) | Custom Home industry — Accessed 2026-09-20
- ADU Laws and Regulations in San Jose (updated Aug 10, 2026) | Steadily industry — Accessed 2026-09-20
- Prefab and detached ADU cost bands, California (updated June 2026) | ADUscale industry — Accessed 2026-09-20
- HUD FY2027 Small Area Fair Market Rents, San Jose-Sunnyvale-Santa Clara, CA HMFA (ZIPs 95110-95148) Government Data — Accessed 2026-09-20
- San Jose, CA rent research (median listing rents, last updated Sept 20, 2026) | Zumper Market Data — Accessed 2026-09-20
- Average Rent in San Jose, CA (last updated Aug 31, 2026) | RentCafe Market Data — Accessed 2026-09-20
- City Council Final Adoption of Ordinances, June 16, 2026 (item 26-740: Ordinance No. 31329 amending SJMC 20.80.178 and 20.80.185) | San José Legistar ordinance — Accessed 2026-09-20
- PP25-007 Title 20 Zoning Code Update State Law Compliance Ordinance, Council memorandum May 19, 2026 (file 26-665) ordinance — Accessed 2026-09-20
- City Council Final Adoption of Ordinances, Feb 3, 2026 (item 26-106: Ordinance No. 31298 amending SJMC 20.80.176, 20.80.177, 20.80.185) | San José Legistar ordinance — Accessed 2026-09-20
- ADU Ordinance & Updates Archive | City of San José Planning Department — Accessed 2026-09-20
Frequently Asked Questions
Can I build an ADU in San Jose?
Yes. ADUs are allowed in Any zoning district where the lot has a legally permitted single-family, duplex or multifamily dwelling (SJMC 20.80.175 A; ADU Universal Checklist, Bulletin #210 rev. Sept 16, 2026, Part 1). An open Code Enforcement case must be closed before plans are accepted. Flood zones A/AE/AH/AO, geohazard, landslide or liquefaction zones, Historic Resources Inventory listing and Wildland-Urban Interface areas add design rules or clearances rather than prohibiting the unit. in San Jose. The maximum size for a detached ADU is Two tracks that cannot be mixed. City standards (SJMC 20.80.175 D.1, Table 20-55): 1,000 sq ft on lots up to 9,000 sq ft, 1,200 sq ft on larger lots, and no cap when converting an existing detached accessory structure. State standards (SJMC 20.80.176 / Gov. Code 66323): 800 sq ft. Minimum 150 sq ft on either track. Square footage is livable floor space measured to the exterior finish; a covered porch or balcony more than 50% enclosed counts (20.80.175 E.3).. Owner-occupancy is not required, so you can rent out the ADU.
How much does an ADU cost in San Jose?
ADU construction in San Jose typically costs $200,000-$450,000. Garage conversions run $90,000-$150,000, and prefab ADUs cost $150,000-$300,000.
How much can I rent an ADU for in San Jose?
Average ADU rents in San Jose are $2,500-$3,000/mo for a 1-bedroom and $3,100-$3,600/mo for a 2-bedroom unit.
Do I need parking for an ADU in San Jose?
None. SJMC 20.80.175 I requires no off-street parking for an ADU and no replacement of covered parking removed to build it; Bulletin #210 (rev. Sept 16, 2026) lists parking as 'None' under both the City and the State standards for single-family, duplex and multifamily lots.. Check with San Jose planning department for the latest California ADU parking rules, as many states have relaxed requirements in recent years.
How long does it take to get an ADU permit in San Jose?
The permit review timeline in San Jose is City-published: the first round of building review typically takes 20 business days and complete plans stay within one or two cycles (ADU FAQs); preapproved plans can be issued the same day as the review meeting. Gov. Code 66317 (SB 543) deems the application approved after 60 days.. Permit fees: FY 2026-27 Building Fee Schedule (effective Aug 10, 2026): ADU 0-750 sq ft $422 issuance + $1,137 plan review + $1,732 inspection = $3,291; 751-1,200 sq ft $633 + $1,950 + $2,520 = $5,103. Excludes construction taxes, school and parkland fees and any planner meeting ($398/hour).
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