Compare ADU rules across Oklahoma

A detached accessory dwelling unit (the code also calls it a guest house or in-law apartment) is listed as 'a permitted use in all residential districts' (RA, RE, RS, RM and RT), but only 'subject to the granting of a Special Zoning Permit' from the Board of Adjustment after a public hearing, so every ADU is a discretionary approval. Section 8.3.4.B expressly allows constructing a detached unit beside an existing house or building a new house with a detached unit. One ADU per single-family lot, the owner must live in the main house, and the unit may not be rented.

Ordinance read October 2026

Internal and attached units take the same route: §8.3.4.B allows converting existing living area, a basement, attic or garage, or adding floor area to an existing detached single-family home, each subject to a Board of Adjustment Special Zoning Permit with a public hearing. An attached unit may have its own entrance only if it faces the interior of the lot.

Ordinance read October 2026

Every ADU needs a Special Zoning Permit from the Board of Adjustment before a building permit can issue: a published newspaper notice, mailed notice to owners within 300 feet, a public hearing (§10.5.6 and §10.5.7) and four findings, including that the use will not be 'injurious to the neighborhood' (§10.5.8). The Board 'may deny an application' or add conditions (§10.5.3). The city's procedure sheet sets a $50 fee, a certified 300-foot owner list and filing 30 days before the monthly hearing; an approval lapses unless a building or zoning compliance permit is applied for within one year (§10.4.6.4).

Ordinance read October 2026

A detached ADU is allowed only by Board of Adjustment special exception after a public hearing. Bixby's zoning code allows no more than one single-family dwelling per lot except for a PUD or an ADU 'approved by special exception' under §11-8-5 (Ord. 2031, 2009). A detached ADU must meet the rules for a detached accessory building, which in residential districts means the rear yard only and at least 5 feet from interior lot lines. Lots under a recorded covenant allowing only one dwelling unit per lot are not eligible.

Ordinance read October 2026

An attached or internal ADU goes through the same special exception route. The definition in §11-2-1 covers a unit 'incorporated within, attached to, or detached from' a single-family home that has its own sleeping, cooking and sanitation facilities. Every ADU is limited to one bedroom and three occupants and must match the main house's exterior materials. The covenant bar also applies to attached ADUs.

Ordinance read October 2026

Every ADU needs a Board of Adjustment special exception. Under §11-4-9 that means a filed application, a public hearing, and approval by a concurring vote of three members after a finding that the ADU 'will be in harmony with the spirit and intent of this title, and will not be injurious to the neighborhood'. The Board must attach conditions. The FY27 fee schedule (updated July 1, 2026) lists a $350 special exception fee and a $150 permit for a new detached accessory building. An approval that is not used within three years is void.

Ordinance read October 2026

There is no attached or internal ADU use either, but a second unit inside or attached to a house is lawful as a two-family dwelling where the district allows one. Sec. 22.9.2 defines a two-family dwelling as one 'designed to be occupied by two families living independently', and it is permitted by right in the B, Two-Family Dwelling district (Sec. 22.4.7) and, as part of 'Household Living', in the C-1, C-2 and C-3 multiple-family districts. Converting a house in an A or estate district requires rezoning to B or C first, a legislative hearing rather than a permit.

Ordinance read October 2026

Enid first allowed accessory dwelling units through Ord. 2026-05 (passed 3-3-2026), which defines an ADU as a detached unit and adds it district by district. It is a by-right permitted use in the A Agricultural, R-1 Estate, R-4A Four-Family, R-5 Townhouse and R-7 Multi-Family districts, but only a use by review in R-2 Single-Family (the most common residential district), R-3 Mobile/Manufactured Home Neighborhood and R-4 Duplex, where the Metropolitan Area Planning Commission must approve it after a posted public hearing. One ADU per lot, located in the rear yard, built to the IRC on a real foundation, compatible with the primary structure.

Ordinance read October 2026

No attached ADU use exists: § 11-1-7 defines an ADU only as a unit 'located on the same lot, as a detached accessory structure from the principal structure', so a basement, internal or attached-addition unit is not an ADU in Enid. The lawful route to a second attached unit is a two-family dwelling (duplex), permitted by right in R-4 and carried into R-4A, R-5 and R-7; in R-1 and R-2 a second attached unit would need a rezoning. Ord. 2026-05 also struck the old R-4 permitted use of 'living quarters above garages' and the 'Apartment Garage' definition.

Ordinance read October 2026

In A, R-1, R-4A, R-5 and R-7 an ADU is a permitted use needing only a building permit and staff review against § 11-14-10. In R-2, R-3 and R-4 it is a use by review: an application to Community Development at least ten days (the city form says two weeks) before a Metropolitan Area Planning Commission public hearing with a posted notice, decided on effect on neighbors, utilities, drainage, parking and traffic, with appeal to the Mayor and Board of Commissioners.

Ordinance read October 2026

No attached ADU use exists: the code defines an Accessory Dwelling Unit as 'a detached residential unit', so an internal or attached second unit has to use another route. A two-family dwelling (duplex) is permitted by right in R-2 and R-3, and in R-1 within the Guthrie Proper Overlay District and the pre-1970 original subdivisions (two units per property on at least 7,000 sq ft), but needs a Special Use Permit (Planning Commission and City Council hearings) in RE and in R-1 elsewhere. A 'garage apartment' above a private garage, which may be attached, is permitted in RE through R-3.

Ordinance read October 2026

Lawton's code has no 'accessory dwelling unit' use. The second-unit route is the garage apartment, defined as 'a dwelling unit for one (1) family erected above a private garage', which is a use by right in the R-2 Two-Family district (and in R-3 and R-4, which inherit R-2 uses) on a lot of at least 7,000 sq ft. The R-1 Single-Family and A-2 Suburban districts, which cover most single-family neighborhoods, list only a detached one-family dwelling plus non-residential accessory buildings, so a backyard unit there needs a rezoning. In the RE Residential Estate district a guesthouse (no rental) may be approved on review on lots of two acres or more.

Ordinance read October 2026

No attached ADU use exists: an R-1 house may contain only one family's dwelling unit, and 'accessory buildings which are a part of the main building' in R-1 are non-dwelling uses such as an attached garage. The route is the two-family dwelling ('a detached dwelling designed to be occupied by two (2) families living independently of each other'), permitted by right in R-2, R-3 and R-4 on a lot of at least 7,000 sq ft, so a house in those districts can be converted or expanded into a duplex. A garage apartment above an attached garage is a further R-2 route the code does not separately address.

Ordinance read October 2026

In R-2, R-3 and R-4 a garage apartment or two-family dwelling is listed under 'uses permitted', so it needs only a building permit and zoning review through the Planning Department. In the RE district a guesthouse is a 'use permitted on review', which §18-1-1-113 equates with a specific use permit under 11 O.S. §43-113: an application to the City Planning Commission with a 300-foot owner notice list and a public hearing, then council action. In R-1 and A-2 there is no route short of rezoning to R-2.

Ordinance read October 2026

Midwest City lists 'Accessory Dwelling Unit, Attached or Detached' as its own residential use unit (§ 4.2.10), and the Table 4.9-1 use chart marks it permitted by right (X) in the A-1, R-35, R-22, R-10, R-8, R-6, R-2F, R-MD and R-HD districts; it is not listed in the manufactured home, mixed-use, office, commercial or industrial districts. A detached ADU, however, needs a lot of at least 12,000 square feet (§ 4.2.10(C)(2)), which is larger than the 6,000, 8,000 and 10,000 square foot minimum lots of the R-6, R-8 and R-10 districts, so many ordinary subdivision lots do not qualify without a variance. Only one ADU per lot is allowed, on the same lot as the main dwelling.

Ordinance read October 2026

The same § 4.2.10 use unit covers attached ADUs: the unit 'may be placed adjacent to the main dwelling, with structural parts touching,' and may be new construction or a converted building such as a garage converted to a garage apartment. It is permitted by right in A-1 through R-HD, but an attached ADU requires a lot of at least 7,500 square feet (§ 4.2.10(C)(1)), so standard R-6 lots (6,000 square foot minimum) do not qualify while R-8 and larger lots usually do. Duplexes (use unit 4.2.2) are a separate by-right use only in R-2F, R-MD and R-HD.

Ordinance read October 2026

Moore has no citywide ADU use. A detached unit is possible two ways. In the Original Townsite (Old Town) and the Electric Addition, §12-408(I) (Ord. 1013.22, 2022) expressly allows ADUs ('carriage houses, granny flats, or garage apartments') in the rear yard, at least 10 feet from the main house. Elsewhere the only route is a 'garage apartment', a dwelling unit built into an accessory building where cars are kept; the R-2, R-3 and R-4 area rules set a 7,500 sq ft lot (and 75 ft frontage in R-2) for a house with a garage apartment, while R-1, RE and the agricultural districts allow only a single-family house on a lot 'unoccupied by any other dwelling unit'.

Ordinance read October 2026

No attached or internal ADU use exists: the Old Town ADU rule places the unit in the rear yard set back 10 feet from the main dwelling, and the garage apartment must sit within a garage building. The lawful route for a second unit inside or attached to a house is a duplex ('Two-family attached residential'), allowed by right in R-2, R-3 and R-4 on a lot of at least 7,500 sq ft with 75 feet of frontage. R-1, the city's most common single-family district, does not allow a duplex.

Ordinance read October 2026

A detached ADU (a unit in an accessory structure on a single-family lot) is allowed only in the A-1 agricultural, R-A and R-1 districts and only through a 'special permit'; it is prohibited in every other district. The unit must be a complete housekeeping unit with kitchen and bath, only one is allowed per lot, its separate entrance must face the interior of the lot, and the structure must match the principal house's materials, roofing, roof pitch, trim and colors.

Ordinance read October 2026

An internal ADU is as of right: §90-12-04.E.3.a lets the Building Inspections Department issue a building permit. A detached ADU needs a 'special permit', which the same clause also has the Building Inspections Department issue, but the zoning code never defines a special permit or a procedure for one. The use tables' 'special' uses go to Board of Adjustment special exceptions after a public hearing (§90-02-05), and Specific Use Permits (Article 23) go to the city council and do not list ADUs. Ask the Planning Department which route applies before you budget for a detached unit.

Ordinance read October 2026

A detached ADU is a listed by-right use only in the A-1, A-2, RE, R-1 and R-1-A districts; the ADU definition itself says an ADU 'may be utilized only within' those five districts, and R-2, RM-2 and R-3 expressly do not inherit the R-1 ADU use. Inside those districts it is routine: one ADU per lot, on the same parcel as the house, no further forward than the principal structure, meeting the district's accessory-building setbacks (in R-1, 5 feet from side lot lines and 1 foot from the rear easement or alley line). The two-family and multifamily districts allow a 'single-family dwelling and a garage apartment' instead, a separately defined use.

Ordinance read October 2026

The ADU definition covers a unit 'attached to the principal dwelling by a common wall or roof', so internal or attached ADUs follow the same district list as detached ones: by right in A-1, A-2, RE, R-1 and R-1-A, not available as an ADU elsewhere. In R-2, RM-2 and R-3 the equivalent second-unit routes are a duplex or a single-family dwelling with a garage apartment (7,000 sq ft minimum lot).

Ordinance read October 2026

Allowed since Ord. No. 27847 (adopted May 20, 2025): a detached Accessory Dwelling (a freestanding unit, or one above or beside a detached garage) is a conditional use in R-1, R-2, R-3, R-4 and NC, but only where the parcel also sits in the Urban Medium or Urban High Land Use Typology Area of the planokc comprehensive plan, which covers the older core of the city rather than its suburban and rural fringe. In R-2, R-3, R-4 and NC the lot must be occupied by a single-family house; the lot must be at least 50 feet wide; and the unit goes in the rear yard meeting district setbacks. It is barred in the Historic Landmark Overlay and the Historic Preservation district (whose use table lists no accessory dwelling and allows one single-family dwelling per lot), and in a PUD or SPUD that does not list it; everywhere outside the UM/UH core an accessory dwelling still needs a rezoning such as a SPUD.

Ordinance read October 2026

The same 9350.2.1 standards allow an attached unit with its own exterior entrance or an internal unit without one, under the same gates as a detached unit: R-1 (or a single-family house in R-2, R-3, R-4 or NC), inside the planokc Urban Medium or Urban High Land Use Typology Area, at least 50 feet of lot width, and outside the Historic Landmark Overlay, the HP district and PUDs or SPUDs that do not list the use. Only one accessory dwelling of any type is allowed per parcel.

Ordinance read October 2026

Not applicable because no ordinary residential district allows an accessory dwelling. For reference, the R-5 condition contains no owner-occupancy rule, while a C-R residential unit 'shall be the primary residence of the owner(s) or primary manager(s) of the commercial use on the property'. Oklahoma has no state owner-occupancy rule for accessory dwellings.

Ordinance read October 2026

Not applicable because no ordinary residential district allows an accessory dwelling. The path to one is discretionary: a Zoning Map Amendment to R-5 (5-acre minimum; Planning Commission recommendation, then a Board of County Commissioners decision after published notice and public hearings under 19 O.S. 868.16), after which the R-5 accessory dwelling is 'P-2' and needs only a building permit from the County Engineer with a site plan and an ODEQ water and sewage certificate. A tiny house needs a Specific Use Permit through the same hearing process, and a temporary hardship manufactured home needs a Board of Adjustment special exception.

Ordinance read October 2026

In R-1, R-2, R-3 and DT-T the use table marks ADUs 'P' (permitted by right, subject to the use-specific standards), so a building permit is the review. In TA, MU and TL-R the table marks them 'C', which requires a conditional use permit: one public hearing, a planning commission recommendation, and a final decision by the city commission by ordinance, with notice to owners within 300 feet. Most in-town single-family lots are zoned R-1 or R-2.

Ordinance read October 2026

No attached ADU use exists. The lawful route to a second attached unit is a two-family dwelling (duplex), permitted by right in the RT Two-Family Residential district (7,500 sq ft minimum lot, 60 ft width) and in the RTM, RMI and NTZ districts, but not in the RSL or RSS single-family districts that cover most neighborhoods. Stillwater defines two-family as two dwelling units 'placed adjacent to one another with structural parts touching' on a lot with no other principal structure, so an attached unit added to a house in RT is built and permitted as a duplex.

Ordinance read October 2026

Tulsa defines an ADU as a dwelling unit in an accessory building (carriage house, garage apartment, mother-in-law flat), one per lot. In the RE and RS single-family districts (RS-1 through RS-5, which cover most Tulsa neighborhoods) and in AG and AG-R, an ADU needs a special exception from the Board of Adjustment after a noticed public hearing. ADUs are allowed by right in RD, RT, RM, RMH and the office, commercial and mixed-use districts when accessory to a household living use, and by right in any district inside the Neighborhood Infill Overlay (NIO), NIO-2 and Neighborhood Character Overlay 2 (NCO-2) areas. The Planning Office's own May 2026 staff summary says Board approvals for ADUs are almost always granted.

Ordinance read October 2026

No attached ADU use exists: Tulsa's ADU definition covers only a unit 'located in an accessory building', so a basement, internal or attached second unit is instead a second household on the lot. 'Two households on single lot' in a duplex building is prohibited in RE, RS-1 and RS-2, needs a Board of Adjustment special exception in RS-3, RS-4 and RS-5, and is permitted by right in RD, RT and RM-0 through RM-3. Duplex lot and building regulations (minimum lot area and the like) then apply in place of the ADU rules.

Ordinance read October 2026

In RE, RS-1 through RS-5, AG and AG-R (most single-family neighborhoods), an ADU is a special exception: an application to the land use administrator, a staff report, newspaper, mailed (300 feet) and posted notice, and a Board of Adjustment public hearing, roughly 40 days minimum per the City's HOME Catalog guide. In RD, RT, RM, RMH, office, commercial and mixed-use districts, and inside the NIO, NIO-2 and NCO-2 overlays, an ADU is permitted by right with a zoning clearance and building permit; a building in a Historic Preservation overlay also needs an HP permit. A floor-area increase beyond the cap is also a special exception.

Ordinance read October 2026

No attached ADU use exists: the only ADU the code defines is a detached accessory structure, and it is allowed only through a PUD or SPUD rezoning. A two-unit house is possible by right as a 'Dwelling, duplex' (a building containing two dwelling units on one lot), which the permitted use table marks P in the R-2 (medium density) and R-3 (multifamily) districts; R-1, A and RR allow only single-family detached homes. In R-2 the lot must have at least 7,000 sq ft and 3,500 sq ft per unit, and duplexes must meet the Sec. 215-509.A design standards (durable exterior materials, no plain concrete block or corrugated metal, garage placement).

Ordinance read October 2026