CheckPre

Sacramento ADU Cost & Permit Fee Calculator

A 600 sq ft ADU in Sacramento runs about $255,000 all in, $8,978 of it city and school fees. Price your own build, fees and rental payback.

Updated · By Niraj Kumar · 11 sources

1. The ADU

Type of ADUType of ADU
sq ft
1501,200

School fees start above 500 sq ft and impact fees at 750 sq ft.

Finish levelFinish level
sq ft

Impact fees from 750 sq ft are scaled by the ADU's size against the house.

2. Site work

ft

Distance from the house's sewer lateral to the ADU.

ft
ft
Main electrical panel upgradeMain electrical panel upgrade
%
0%25%

Architect, structural engineer, Title 24 and survey, as a share of the build. About 4% with a city pre-approved plan.

%
0%30%

3. Sacramento fees

$

Sacramento fee schedule.

$

Waived: under 750 sq ft (state law).

$

Charged on new detached and attached units.

$

$5.38 a sq ft on the whole unit.

4. Rent and financing

Rented asRented as
$

HUD's FY 2026 fair market rent for the metro, a conservative figure. Enter a local listing to replace it.

%
0%50%
%

Charged on the ADU's construction cost only; the house is not reassessed.

$
% of rent
0%30%
How you payHow you pay
years
5 yrs30 yrs
%

Net rent ÷ cap rate is how appraisers value income. 4-6% is typical for California rentals.

Total cost, Sacramento$255,361$426 a sq ft, $8,978 of it fees

At 500 sq ft it would pay no school fees, saving $3,228.

Construction
$246,383
build, site work, design and contingency
City and school fees
$8,978
Monthly cash flow, year one
$1,091
on $1,600 rent
Payback
15.4 years
5.1% cash-on-cash in year one
Value added
$261,876
$6,515 more than it costs, at a 5% cap rate
Where the money goes600 sq ft detached ADU, standard finish
  1. 1Construction$199,500
  2. 2Contingency$20,948
  3. 3Design and engineering$15,960
  4. 4Utility trenching$9,975
  5. 5Permit and plan check$3,250
  6. 6School fees$3,228
  7. 7Sewer and water capacity$2,500
Cumulative cash flow from rentStill to recoverAhead
$-300 K$-200 K$-100 K$0$100 K$200 KPayback, year 15.4048121620
Year-by-year rent and cash flowShow
YearRent collectedRunning costsLoanCash flowCumulative
1$18,240$5,146$0$13,094-$242,267
2$18,787$5,273$0$13,514-$228,753
3$19,351$5,404$0$13,947-$214,806
4$19,931$5,538$0$14,393-$200,413
5$20,529$5,675$0$14,854-$185,559
6$21,145$5,816$0$15,329-$170,230
7$21,780$5,961$0$15,819-$154,411
8$22,433$6,109$0$16,324-$138,088
9$23,106$6,261$0$16,845-$121,243
10$23,799$6,417$0$17,382-$103,861
11$24,513$6,578$0$17,936-$85,926
12$25,248$6,742$0$18,507-$67,419
13$26,006$6,910$0$19,096-$48,324
14$26,786$7,083$0$19,703-$28,621
15$27,590$7,261$0$20,329-$8,292
16$28,417$7,443$0$20,975$12,683
17$29,270$7,630$0$21,640$34,323
18$30,148$7,821$0$22,327$56,649
19$31,052$8,018$0$23,034$79,684
20$31,984$8,220$0$23,764$103,448

How the Sacramento ADU Cost & Permit Fee Calculator works

A new 600 sq ft detached ADU in Sacramento costs about $255,000 to build in 2026, including $8,978 in permit, capacity and school fees. Impact fees do not apply under 750 sq ft. Rented at $1,600 a month, it pays back in about 15 years.

Cost = sq ft × rate₍type, finish₎ × city index + utility runs + panel + design + contingency + fees fees = permit + impact × (ADU ÷ house, from 750 sq ft) + capacity (new builds) + school × sq ft (over 500) Payback: Σ₍y₎ (rent × (1 − vacancy) − tax − insurance − upkeep − loan) ≥ cash invested

This page uses the same method as the California ADU Cost & ROI Calculator, which explains each term and assumption in full.

Worked example

A 600 sq ft detached one-bedroom ADU at standard finish behind a 1,600 sq ft house in Sacramento, with utility lines run 50 ft from the house, paid in cash.

  1. 1Construction: 600 sq ft at about $333 a sq ft is $199,500; utility trenching adds $9,975, design $15,960 and a 10% contingency $20,948
  2. 2Fees: $3,250 in permit and plan check, no impact fees (under 750 sq ft), $2,500 in sewer and water capacity, and $3,228 in school fees
  3. 3Rent of $1,600 a month less 5% vacancy, property tax, insurance and upkeep leaves $13,094 a year

The ADU costs about $255,361 all in, $426 a sq ft, of which $8,978 is fees. The rent repays it in about 15.4 years, a 5.1% cash return in the first year.

Frequently asked questions

How much are ADU permit fees in Sacramento?

For a new 600 sq ft detached ADU, city and school fees come to about $8,978: $3,250 in permit and plan check, $2,500 in sewer and water capacity charges and $3,228 in school fees. At 800 sq ft they rise to about $14,304, including $3,000 in impact fees. Going from 749 to 750 sq ft alone adds about $4,068. A garage conversion pays a smaller permit fee and no capacity charge.

How much does it cost to build an ADU in Sacramento?

About $255,000 for a 600 sq ft detached ADU at standard finish, all in, or $426 a sq ft, and about $339,000 for 800 sq ft. Rented as a one-bedroom at $1,600 a month, the HUD fair market rent for the area, it would repay a cash build in about 15.4 years. A garage conversion typically costs 35-45% less.

What is unusual about ADU fees in Sacramento?

City fees for a small ADU add to about $3,250: building permit, planning and utilities review, construction excise tax, general plan, residential construction and technology fees. Regional sewer (SacSewer) and school fees are collected separately; the impact and sewer figures are estimates.

Sources

Related calculators

More in Construction & DIY