How Much Does an ADU Cost in Sacramento? (2026 Guide)

If you're thinking about an accessory dwelling unit in Sacramento, the first question is almost always the same: what will it cost? Here are the typical 2026 price ranges we see as a licensed ADU builder in Sacramento — and what pushes a project to the low or high end.

Sacramento ADU cost at a glance (2026)

These are ranges, not quotes. The only way to get a real number for your property is a walkthrough and a written, fixed price.

A range that wide isn't a dodge. Two ADUs of the same type can land far apart because of the lot they sit on, the utilities they need, and the choices you make along the way. The rest of this guide walks through what actually moves the number, so you can see where your project is likely to fall before anyone draws a plan.

The four kinds of ADU, and why they cost different amounts

Detached ADU

A detached ADU is a brand-new, separate home in your backyard, with its own kitchen, bathroom, and entrance. It can be one or two stories. Because everything is new — foundation, framing, roof, windows, plumbing, electrical, and every finish — it usually sits at the top of the cost range. It's also the most flexible option: you choose the size, the layout, and where it goes on the lot, within what the city allows.

Attached ADU

An attached ADU is built onto your existing house and has its own entrance. It's a good fit when the backyard is tight. You may save some exterior work because the unit shares a wall with the house, but the new structure has to tie cleanly into your existing roof, foundation, and systems, and that connection takes care and engineering.

Garage conversion ADU

A garage conversion turns an existing garage into a legal living unit. It's usually the most budget-friendly way to add an ADU because the slab, walls, and roof are already there. You still need insulation, windows, plumbing, electrical, a kitchen, and a bathroom, and the existing structure has to be brought up to code for living space. Some garages need much more of that work than others, which is why we look at the garage itself before giving a number.

Junior ADU (JADU)

A JADU is a junior unit of up to 500 square feet carved out of your existing home, with an efficiency kitchen. Because it works inside walls you already have, the scope is often smaller than a full ADU. It still depends heavily on the space you're converting, so we price JADUs after a walkthrough rather than publishing a range.

What drives ADU cost in Sacramento

1. Size and layout

More square feet means more of everything: foundation, framing, roofing, flooring, drywall, and paint. Bedrooms and bathrooms matter even more than raw size. Each bathroom adds plumbing, waterproofing, tile, and fixtures, and a second story adds structure and stairs. A simple rectangular footprint with the kitchen and bathroom sharing a wall is the most cost-efficient layout to build.

2. Site work

What's on your lot before construction starts can move the price as much as the building itself. We look at access for equipment and materials, slope and drainage, trees, and anything that has to come out first, like an old shed or a concrete slab. A flat, open backyard with a clear path from the street costs less to build on than a tight lot where everything has to be carried in.

3. Utilities

Every ADU needs water, sewer, and electrical service, and this is where surprises most often hide. Common upgrades include a bigger electrical panel or service, a new or longer sewer connection, and trenching from the main house to the unit. The farther the ADU sits from your existing lines, the more trenching it needs. If you want separate meters for the unit, that adds work too. We check your panel and utility locations at the first walkthrough because they're the most common reason ADU budgets grow.

4. Design, engineering, and permits

Before anything is built, you need a set of plans the city will approve. That usually includes a site plan and floor plan, structural engineering where needed, and California energy-code (Title 24) documentation for the new living space. The city also charges fees for plan review and permits, and depending on the project and the jurisdiction there may be other fees, such as utility connection fees. These costs vary by property, so ask any builder you talk to which of them are included in their price — and get the answer in writing.

5. Finishes

Cabinets, counters, flooring, tile, plumbing fixtures, lighting, appliances, and windows all come in a wide range of prices. Two ADUs with the same floor plan can differ by a lot depending on what goes inside. Choosing your finishes before the price is final is the best way to make sure the number you sign is the number you pay.

How the Sacramento ADU permit process works

Every city and county around Sacramento runs its own review, so the exact steps and paperwork depend on where your property is. California has passed a series of laws in recent years to make ADUs easier to permit statewide, but local rules still matter. In general terms, the process looks like this:

1. Feasibility and walkthrough. Confirm that your lot can fit the kind of ADU you want, and check setbacks, access, and where utilities can connect.
2. Design and plans. Turn the idea into a site plan, floor plan, and the engineering and energy documents the city requires.
3. Plan submittal and review. The plans go to the city for review. It's common for the city to send back corrections; those get answered and the plans are resubmitted.
4. Permit issued. Once the plans are approved and fees are paid, the permit is issued and construction can start.
5. Construction and inspections. The city inspects the work at set stages, such as foundation, framing, rough plumbing and electrical, and insulation, before the walls are closed.
6. Final inspection. After the final inspection passes, the ADU is a legal, permitted unit.

How long all of this takes depends on the type of ADU, how quickly plan review moves, and how much site work your lot needs, so we don't guess at a timeline before we've seen the property. After the walkthrough, your scope comes with a written schedule. We handle the applications, plan check corrections, and inspections, so you don't have to chase the city.

Ways to keep your ADU budget under control

• Pick the type that fits your lot. If you have a solid garage, a conversion is often the most affordable path. If you need a separate home, a detached ADU gives you the most freedom.
• Keep the layout simple. A rectangular footprint and a kitchen that shares a wall with the bathroom keep plumbing runs short.
• Find utility issues early. Know the age and size of your electrical panel and sewer line before design is finished.
• Decide finishes up front. Changes after the price is set are the easiest way for a budget to drift.
• Get one fixed price in writing. Any change after that should be a signed change order, priced before the work is done.
• Know the payment rules. On a home improvement contract, California law caps the down payment at $1,000 or 10% of the contract price, whichever is less. After that, you should pay as each phase is finished, not ahead of the work.

ADU planning checklist

Bring answers to as many of these as you can to your first walkthrough:

• What will the ADU be used for: family, rental income, or a home office?
• Which type fits: detached, attached, garage conversion, or JADU?
• How many bedrooms and bathrooms do you need?
• Is there a clear path into the backyard for equipment and materials?
• Where are your electrical panel, sewer line, and water line, and how old are they?
• Do you want separate utility meters for the unit?
• Are there trees, sheds, or slabs that would need to come out?
• What budget range are you working with, and how will you pay for it?
• Are design, engineering, permits, and city fees included in the price you're quoted?
• Is the contractor licensed? Look up the license number on the CSLB website.

ADU cost questions, answered

Get a real number for your lot

We'll walk your property, check access, utilities, and setbacks, and give you one clear, fixed ADU price — in writing. Learn more about our ADU building services in Sacramento, or see the kinds of projects we build.