In short
- 114 ADU permits since 2018.
- 16 in 2025.
- Typical permit time: 133 days from application to permit (median of 51 permits with both dates recorded).
About this data
- Source: California HCD Housing Element Annual Progress Reports. The state data does not say whether an ADU is detached, attached, a garage conversion or a JADU, so most records show as 'unknown'. Permit valuations are not published in this source. Timelines use the application date the city reported to the state, matched to the permit where possible; some cities report their planning application date, so timelines can include planning review. Each project is counted once, in its building-permit year (or completion year when no permit date was reported).
Permits by year
Permits by year and type (table)
| Year | All ADU permits | Garage conversions | Detached |
|---|---|---|---|
| 2018 | 14 | — | — |
| 2019 | 13 | 1 | 0 |
| 2020 | 7 | 2 | 0 |
| 2021 | 20 | 1 | 1 |
| 2022 | 18 | 0 | 8 |
| 2023 | 12 | — | — |
| 2024 | 14 | — | — |
| 2025 | 16 | — | — |
“—” means the source for that year does not report ADU type.
Read more: ADU types explained
Not counted above: 3 approved projects with no building permit reported yet.
ADU rules in Coronado
State law check: HCD found the city's ADU ordinance (No. 2024-02) out of line with state law (December 10, 2025), including its parking, survey, size and unit-count rules; the city responded and plans amendments.
| Rule | Coronado's code | State law guarantees |
|---|---|---|
| Maximum size | 850 sq ft (studio or 1 bedroom) or 1,000 sq ft (more than one bedroom), attached or detached, within the zone's floor-area limit (an 800 sq ft ADU is always allowed). Junior ADU 500 sq ft. | At least 850 sq ft (1,000 sq ft with 2+ bedrooms) must be allowed; an 800 sq ft detached ADU always is. Conversions of existing space have no size cap. Junior ADU: up to 500 sq ft. |
| Height | Detached: 16 ft (18 ft near major transit, plus 2 ft for a matching roof pitch). Attached: the house's height limit. | Detached: at least 16 ft (18 ft within ½ mile of transit, plus 2 ft for a matching roof). Attached: 25 ft or the zone's limit, whichever is lower. |
| Setbacks | 4 ft side and rear (or the zone's, if less). None for conversions or same-footprint rebuilds, which need before-and-after land surveys. | No more than 4 ft side and rear; none for conversions of existing space. |
| Parking | 1 space per ADU (none if deed-restricted affordable); replacement parking when a garage is converted. None for junior ADUs. | At most 1 space; none within ½ mile of transit and in several other cases. No replacement parking when a garage is converted. |
| Owner living on site | No owner rule for ADUs, but a recorded covenant is required. Junior ADU: the owner lives in the house or the junior ADU. | None for ADUs. A junior ADU that shares a bathroom with the house requires the owner to live in one of them. |
| How many on a single-family lot | One ADU or one junior ADU per single-family lot, or a new ADU of up to 800 sq ft plus a junior ADU. | One ADU converted from existing space, one junior ADU and one new detached ADU (up to 800 sq ft). From January 1, 2027: two new detached ADUs (a city then needn't allow a junior ADU on that lot). |
| Short-term rentals | Six consecutive months or more, for ADUs and junior ADUs. | No guarantee: cities may require rentals of more than 30 days, and junior ADUs can't be short-term rentals. |
- The whole city is in the Coastal Zone; the city cites its Local Coastal Program for its parking rules.
- ADUs must match the house's architectural style, materials and colors.
- Carriage house ADUs (CMC 86.56.110): a garage with up to 400 sq ft of living space above, on lots with street and alley access.
- The city runs a pre-approved ADU program and an affordable ADU program.
Where local rules conflict with state law, state law controls. Sources: Coronado Municipal Code 86.56.105 · HCD findings (December 10, 2025); HCD's list of review letters; California ADU rules. Verified Oct 5, 2026. Rules change and every lot is different: confirm with the city before you design.
How long permits take
| Type | Median days, application to permit | Middle half | Permits |
|---|---|---|---|
| Detached ADU | too few to say | 3 | |
| Attached ADU | too few to say | 3 | |
| Garage conversion | too few to say | 2 | |
| Junior ADU (JADU) | too few to say | 2 | |
| Unclassified | 136 | 95 – 345 | 41 |
Middle half: the range covering the middle 50% of permits (a quarter were lower, a quarter higher).
Read more: How long ADUs take to build
From permit to completion
Of the 50 ADU permits Coronado reported issuing from 2020 through 2023, 15 (30%) have a completion reported to the state.
The state reports don't record expired or cancelled permits, and a completion the city hasn't reported looks the same as an unfinished project, so the share is a floor. Years with incomplete reports are left out.
What neighbors declared as cost
Cost data (declared permit valuations) is not published for this area in these sources.
Read more: How to choose an ADU builder
An ADU builder serving Coronado? Feature your business on this page.
Questions about ADUs in Coronado
How many ADUs have been permitted in Coronado?
Public records show 114 ADU permits in Coronado from 2018 through 2025. 16 in 2025. These counts come from the city's reports to the state, which place a project in its completion year when no permit date was reported.
How long does an ADU permit take in Coronado?
Among the 51 ADU permits in Coronado with both dates recorded, half were issued within 133 days of the application; the middle half took 100 to 270 days. That includes plan-check corrections and resubmittals, not just the review itself.
Can I build an ADU on my property in Coronado?
California law allows ADUs on most lots with a house, including in Coronado, but what you can build depends on your lot, local rules and utilities. This site shows permits, not eligibility. See California ADU rules.
Where do I apply for an ADU permit in Coronado?
Apply with the City of Coronado's Community Development Department, which also runs a pre-approved ADU program. Official ADU page.
How current is this?
- State annual progress reports: through 2025 (published once a year)
How our data works · Download the data · Free to reuse with credit to SoCal ADU Tracker (socaladutracker.com), under CC BY 4.0.