What's Required in Sacramento
- Every ADU needs a building permit; choose Local or State standards and mark it on the plan cover sheet.
- Local: two ADUs; detached total 1,200 sq ft; attached 50 percent of the house, 850 sq ft or 1,000 sq ft with 2+ bedrooms.
- Local: 3-foot interior side and rear setbacks within 60 feet of the front line; 4 feet between detached units and the house.
- State: detached ADU up to 800 sq ft and 18 feet, with 4-foot side and rear setbacks; junior ADU up to 500 sq ft.
- Development impact fees are waived at 749 square feet or less; school impact fees still apply.
- Each ADU needs its own address; a separate water meter tap is not required.
- Detached ADUs up to 1,200 sq ft are exempt from fire sprinklers if the main home is not sprinklered.
- Only one ADU is allowed per lot in the EA-2 or EA-3 overlay zones.
How much does an ADU permit cost in Sacramento?
The City of Sacramento Community Development Department publishes its own ADU fee estimate (CDD-0419, revised July 12, 2026) for new construction valued at $170.80 per square foot. The approximate totals are $5,271.90 for a 749 sq ft ADU, $10,624.40 at 750 sq ft and $14,842.50 at 1,200 sq ft. The jump at 750 is state law: development impact fees are waived for an ADU of 749 square feet or less, and the park ($2,617.50 at 750 sq ft), flood control ($1,575) and transportation ($1,154.64) fees switch on at 750. Every size pays building permit and plan review fees ($1,267.56 and $532.37 at 749 sq ft), Fire Department administrative, inspection and plan review fees, a Planning inspection fee ($526) and Planning review ($263), plus the excise, General Plan, green building, strong motion and technology fees. Not included: school impact fees, paid at your school district, and regional sanitation and sewer fees, which the estimate says to check with the County. Owner-builders do not pay the business operations tax. The city calls these figures an estimate; your invoice depends on scope and location.
What size ADU can you build in Sacramento?
You choose between two rulebooks and mark the choice on your plan cover sheet. Under the city’s Local ADU Ordinance (City Code 17.228.105(B)) a lot may have two ADUs in any combination; detached ADUs may total 1,200 square feet; an attached ADU may be 50 percent of the house, 850 square feet, or 1,000 square feet with two or more bedrooms, whichever is greater; height follows the zone (35 feet in R-1); interior side and rear setbacks are 3 feet if any part is within 60 feet of the front property line, none for a first floor set at least 60 feet back, and 3 feet for upper floors; detached units stay 4 feet from each other and the house. Under the State ADU Standards (17.228.105(C) and Government Code 66323) a single-family lot may have one attached conversion, one junior ADU of up to 500 square feet and one detached ADU of up to 800 square feet, 18 feet tall (plus 2 feet to match the roof pitch), with 4-foot side and rear setbacks, and short-term rental is prohibited.
| What you are doing | City filing | Rule |
|---|---|---|
| Detached ADU up to 749 sq ft | Building permit, impact fees waived | CDD-0419 estimate about $5,271.90 |
| Detached ADU 750 to 1,200 sq ft (Local) | Building permit plus impact fees | About $10,624.40 at 750 sq ft, $14,842.50 at 1,200 |
| Detached ADU under State Standards | Building permit | 800 sq ft, 18 ft, 4 ft side and rear setbacks |
| Attached ADU (Local) | Building permit | 50% of the house, 850 sq ft, or 1,000 sq ft with 2+ bedrooms |
| Junior ADU inside the house | Building permit, deed restriction | 500 sq ft; owner occupancy if sanitation is shared |
| Garage conversion | Residential Remodel permit | Valued at $101.16 per sq ft; may be routed to Fire |
| Lot in the EA-2 or EA-3 overlay | Building permit | Only one ADU per lot |
How do you get an ADU approved?
A building permit is required for every ADU. The ADU Resource Center says no separate Planning approval is needed before you apply and offers a free Optional Zoning Review (1 to 3 weeks); the Building Division’s ADU handout (CDD-0423) still says Planning approval or concurrent review must come first, so ask which applies when you submit. State law gives the city 60 days to approve or deny a complete application on a lot with an existing home; the city quotes roughly 1.5 to 2 months of building plan review, with 20, 15 and 5 business-day cycles. The city’s free shelf-ready plans (studio 367, one-bedroom 559 and two-bedroom 747 habitable square feet, all-electric) cannot be modified, though they can be mirrored. No owner-occupancy is allowed to be required for an ADU, ADUs may be rented but not sold separately, each ADU needs its own address (allow up to four weeks), and a separate water meter tap is not required. Lots outside city limits follow Sacramento County’s ADU rules instead.
How to Get a ADU Permit in Sacramento
Check your lot
Confirm the lot is in the City and look up its zone, overlays and any historic district in the Land Information Lookup App.
Pick Local or State standards
Compare size, height and setback limits, then design to one set; consider the free shelf-ready plans.
Optional zoning review
Submit the free ADU Optional Zoning Review (CDD-0009) if you want Planning to check zoning first; it takes 1 to 3 weeks.
Submit the building permit
Upload plans, the application and an address request through the Public Permit Portal; review runs in 20, 15 and 5 business-day cycles.
Pay fees and build
Pay the invoiced city fees and school impact fees, then pass foundation, framing, insulation and final inspections before occupancy.