What ADU contractors charge in 2026, how to vet one, and where the bids differ. Real line-item pricing, not a range.
If you are searching for adu contractor, you have already made the decision to build. What is left is choosing who builds it, and that choice is usually made on a number that is not comparable between bids. This page publishes ours.
An accessory dwelling unit is a second, self-contained living unit on a lot that already has a primary home — the industry term for what most people call a granny flat, in-law suite, backyard cottage, casita or garage apartment. It has its own kitchen, its own bathroom, its own entrance, and in most jurisdictions its own address and utility meter.
Three forms exist and they are not interchangeable on cost. A detached unit is a separate structure in the yard and is where factory-built wins hardest, because the whole building arrives finished. An attached unit shares a wall with the main house and carries structural tie-in work. A conversion turns an existing garage or basement into a dwelling and looks cheap until you price bringing an uninsulated slab, a low ceiling and a non-conforming header up to habitable code.
Published pricing against a national builder's own published pricing.
| Footprint | Layout | Our turnkey | National builder published | Difference |
|---|---|---|---|---|
| 385 sq ft | Studio | $232,000 | $298,800 | $66,800 |
| 500 sq ft | 1 bed / 1 bath | $253,000 | $324,800 | $71,800 |
| 640 sq ft | 1 bed + office | $278,000 | — | — |
| 800 sq ft | 2 bed / 2 bath | $312,000 | $424,800 | $112,800 |
| 1,000 sq ft | 2 bed + great room | $341,000 | — | — |
| 1,195 sq ft | 3 bed / 3 bath | $374,000 | $498,800 | $124,800 |
Comparison column reflects a national turnkey ADU builder's own published fixed-price list as of 2026. Both columns are all-in scopes covering design, permitting, foundation, delivery, set and utility connection. Our figures are budgeting estimates; a confirmed number requires a site address.
The base rate moves with the specification, not with the sales conversation.
| Finish tier | Base rate | What it includes |
|---|---|---|
| Essential | $265/sq ft | Painted drywall, LVP flooring, stock cabinetry, standard appliance package, single-hung windows |
| Signature | $325/sq ft | Quartz counters, tile wet areas, soft-close cabinetry, stainless appliances, black-framed sliding glass |
| Premium | $395/sq ft | Full-height tile, custom millwork, panel-ready appliances, wide-format glazing, cedar soffit detailing |
These are real and they are yours whether or not the quote mentions them.
| Line item | Typical cost | What drives it |
|---|---|---|
| Foundation | $38–52 per sq ft | Pier and beam at the low end, full stem wall or slab at the high end. Soil type and frost depth decide. |
| Site survey | $5,400 | Required before permit in nearly every jurisdiction. Locates setbacks, easements and utility runs. |
| Permitting | $8,900 | Plan review, permit issuance and inspection fees. Ministerial-approval states run lower. |
| Lot clearing | $4,200 | Vegetation removal and grading for the pad and the crane or truck path. |
| Utility trenching | $185 per linear foot past 50 ft | Water, sewer and electrical from the main house or the street. This is the line most quotes omit. |
| Crane set | $8,600 | Required when truck access cannot reach the pad, or for any second-story module. |
| Freight | $6.80 per loaded mile | From the fabrication facility to your address. Long hauls and permit loads add escort cost. |
| Utility connection | $3,800–11,400 | Meter, panel and tie-in. Varies most with distance and whether a service upgrade is triggered. |
The reason two ADU bids can differ by sixty thousand dollars on identical units is almost never the building. It is which of the rows above sit inside the number and which arrive later as change orders. When you compare bids, the only question worth asking is: which of these eight lines is included, and at what allowance?
Seven questions separate a real operation from a broker with a website:
Slot-based, not a fixed promise.
A factory runs a queue. When you reserve a slot you are buying a position in that queue, and the honest answer to "how fast" depends on three things: how many slots are already committed, the lead time on the specific materials your configuration calls for, and whether your permit clears before your slot opens.
Current windows run 30 to 90 days from released engineering to delivery for standard configurations. Smaller units with Essential finishes sit at the fast end. Anything with a ballistic package, a hurricane-rated envelope, custom glazing or a second story sits at the slow end because those components have their own supply lead times.
The reason this beats a site-built schedule is not that the factory works faster on any given day. It is that permitting and fabrication run in parallel instead of in sequence, and the on-site set is measured in hours rather than months. Weather stops a framing crew; it does not stop a production line.
Windows move with demand and material availability. A slot quoted today holds while capacity lasts.
Fifteen states have statutes that materially change what you can build. These are the ones where the law, not the local planner, decides.
Tell us the scope and the ZIP. You get a real delivered-and-installed number, not a "contact us for pricing" runaround.
We run a group of focused sites so you land on the one that matches what you actually need instead of a catch-all catalog.