Skip to content
UpsideADU
Cost

How Much Does an ADU Cost in Sacramento?

Updated June 12, 2026 · Upside ADU

Quick answer

A detached ADU in Sacramento costs about $165,000–$500,000 in 2026, or roughly $250–$360 per square foot turnkey (design, permits, and construction included). Garage conversions start near $95,000 and Junior ADUs near $85,000. A 750 sq ft 2-bedroom unit at mid-range finishes runs roughly $230,000–$300,000.

How much does an ADU cost by type in Sacramento?

ADU price is driven first by type, because type decides how much new structure you build. Reusing an existing slab and walls (garage conversion) or existing interior space (Junior ADU) is far cheaper than pouring a new foundation and framing a standalone building. The table below is market-wide for the Sacramento region in 2026 — not a single builder's price list.

Sacramento ADU cost by type — 2026 market ranges

ADU typeTypical size$ / sq ftTurnkey range
Junior ADU (JADU)≤500 sq ft$170–$360$85,000–$180,000
Garage conversion350–700 sq ft$190–$360$95,000–$250,000
Attached ADU500–900 sq ft$230–$360$150,000–$320,000
Detached ADU500–1,200 sq ft$250–$360$165,000–$500,000

See also:Upside's published pricing — our actual prices by type · Estimate your build — interactive calculator

What's included in a turnkey ADU price?

A real turnkey number covers five cost buckets: design and engineering, permits and city fees, site prep and utilities, the building shell, and interior finishes. The single biggest cause of budget blowups is a quote that quietly excludes site work or utility connections — that's where surprise change orders hide. Always ask a bidder to itemize all five. California's ADU law waives local impact fees for units under 750 sq ft (per California HCD), which is why unit size has an outsized effect on the bottom line.

  • Design + engineering: architectural plans, Title 24 energy, structural calcs
  • Permits + fees: $5,000–$25,000 by jurisdiction (impact fees waived under 750 sq ft)
  • Site prep + utilities: grading, foundation, and sewer/water/electrical trenching
  • Construction: framing, roof, windows, mechanical, electrical, plumbing
  • Finishes: flooring, cabinets, countertops, fixtures, appliances

What does an ADU cost per square foot?

Cost per square foot is the cleanest way to compare ADU bids, but smaller units cost more per foot. Fixed costs — a kitchen, a bathroom, a utility hookup, a permit — get spread across fewer square feet, so a 400 sq ft studio can run $340/sq ft while a 1,000 sq ft two-bedroom lands closer to $270/sq ft for the same finish level.

Estimated turnkey cost by size at mid-range finishes (2026)

SizeTypical config$ / sq ftEstimated turnkey
400 sq ftStudio / JADU$300–$360$120,000–$165,000
600 sq ft1 bedroom$270–$340$165,000–$215,000
750 sq ft2 bedroom$255–$320$230,000–$300,000
1,000 sq ft2–3 bedroom$250–$310$250,000–$340,000

What drives your ADU budget up or down?

  • Size: keeping the unit just under 750 sq ft avoids impact fees entirely
  • Site conditions: slope, poor soil, and long utility runs add cost (common in Folsom, Auburn, El Dorado Hills)
  • Finish level: standard vs. premium finishes can swing $40–$80 per sq ft
  • Detached vs. conversion: reusing a garage slab is the cheapest structural path
  • Design path: a pre-approved or shelf-ready plan set is cheaper and faster than full custom

What hidden costs should you budget for?

The sticker price isn't the whole picture. Budget a contingency of 10–15% and account for the items below — they're legitimate, common, and routinely left off lowball bids. A complete bid that names these line items up front is worth more than a cheaper one that doesn't.

  • Utility connections: a new sewer lateral or electrical panel upgrade can add $5,000–$20,000
  • Site work: grading, drainage, tree removal, and retaining walls on sloped lots
  • Soils report and survey on lots that require them
  • Fire sprinklers if the main house already has them or local code triggers them
  • Driveway, fencing, and landscaping to make the unit livable and rentable

Why are Sacramento ADU costs lower than coastal California?

Two regional factors keep Sacramento ADU costs below coastal California. First, lots here are generally flatter and larger than in the Bay Area, so site work is cheaper. Second, the City of Sacramento and Sacramento County both publish pre-approved ADU plan sets that trim design and plan-check cost (see City of Sacramento Community Development). Where costs climb is the foothill submarkets — Folsom, El Dorado Hills, Auburn — where slope and rock raise foundation and trenching costs.

How does ADU cost vary across the Sacramento region?

Where you build inside the four-county region shifts the budget even when the unit is identical. Flat infill lots in the city core and the I-80 / Highway 50 suburbs sit at the lower end because site work is simple and pre-approved plans are common. Foothill submarkets run higher because slope, rock, and longer utility runs raise foundation and trenching costs. The building itself costs about the same to frame and finish; what moves is the site work beneath it.

Relative ADU site-cost by Sacramento submarket (2026)

Submarket typeExamplesRelative build cost
Flat infill / coreSacramento, Citrus Heights, Rancho CordovaLowest
Established suburbElk Grove, Roseville, Rocklin, Folsom (flat)Low–mid
Foothill / slopedEl Dorado Hills, Auburn, Cameron Park, LoomisMid–high

See also:ADU costs & rules by city — pick your city for local pricing · ADU builder in Sacramento

How does an ADU compare in cost to a home addition?

Homeowners weighing an ADU often price a home addition at the same time. A basic addition can be a bit cheaper per square foot because it shares walls and systems with the existing house, but it can't be rented as a separate unit. The full decision — cost, permits, rentability, and resale value — is broken down in our dedicated comparison.

See also:ADU vs. home addition in Sacramento

How do you get an accurate ADU quote?

The most reliable number comes from a fixed-price, itemized turnkey bid — not a per-square-foot rule of thumb. Ask any builder to put all five cost buckets in writing, name the finish allowances, and state exactly what triggers a change order. A bid that itemizes site work and utility connections up front is worth more than a lower bid that leaves them as vague 'allowances' to be priced later.

  • Insist on one turnkey figure that includes design, permits, site work, construction, and finishes
  • Get finish allowances in writing (flooring, cabinets, counters, appliances)
  • Ask which soil, utility, or panel-upgrade conditions could change the price
  • Compare bids at the same scope — not one with utilities and one without
  • Confirm the payment schedule: California caps the down payment at $1,000, then inspection-tied milestone draws

See also:Upside's published pricing — fixed prices by type · Get a free feasibility check

What are the most common ADU cost mistakes?

  • Comparing bids that aren't all turnkey — one excludes utilities, another includes them
  • Ignoring the impact-fee cliff by designing a unit at 760 sq ft instead of 740
  • Assuming the CalHFA $40,000 grant is still available — it is exhausted
  • Skipping the contingency line and treating the bid as a fixed ceiling
  • Choosing the lowest $/sq ft without checking the finish level it assumes

See also:How to finance an ADU in California · Does an ADU raise property tax?

This guide is general information, not legal or tax advice. ADU rules change often and vary by city — we confirm the current requirements for your jurisdiction during your free feasibility check.

Sources & references

External links open official government and lender resources. Construction price and rent figures reflect 2026 Sacramento-region market conditions; confirm current rules and fees with your jurisdiction.

Frequently asked questions

Most Sacramento ADUs cost $165,000–$500,000 in 2026 depending on size and type. Garage conversions are cheapest (from ~$95,000), detached units cost the most, and mid-range builds run $250–$360 per square foot turnkey including design, permits, and construction.

A Junior ADU built inside your existing home is the cheapest (from ~$85,000), followed by a garage conversion that reuses an existing slab and walls (from ~$95,000). Both avoid the cost of a new foundation and full structural framing.

Roughly $250–$360 per square foot turnkey in 2026 at mid-range finishes. Smaller units cost more per foot because fixed costs — kitchen, bath, utilities, permits — spread across fewer square feet, so a 400 sq ft studio can exceed $340/sq ft.

The most common surprises are utility connections, site grading, and city fees. A complete turnkey bid should itemize all five cost buckets — design, permits/fees, site/utilities, construction, and finishes — and you should add a 10–15% contingency on top.

Yes. ADUs under 750 sq ft are exempt from local impact fees, which can save several thousand to over $20,000 depending on the jurisdiction. Many Sacramento owners deliberately size a unit just under that threshold to capture the exemption.

Related tools & pages

Related guides

Ready to see what your backyard could earn?

Get a transparent, all-in quote and a feasibility check for your specific lot — usually within a few days.

CallFree Estimate