Accessory dwelling unit in Seattle

A State-by-State Guide to Zoning Reform

By Anthony Flint, December 23, 2022


Statewide measures to change zoning at the local level have passed or are under consideration in several states. The aim is to allow a range of more affordable housing options and to create more equitable and sustainable communities. Opposition based on the tradition of local control over land use has been building, however. Find out more about current reform efforts below, and read our article The State of Local Zoning to learn more about the history of zoning and the reasons behind the push for reform.

Arizona. State representatives César Chávez (D) and Steve Kaiser (R) introduced a bill in 2022 allowing multifamily housing or increased single-family-home density on land zoned for agriculture or single-family homes. Following fierce opposition, the proposal was rewritten to establish a committee to study housing supply.

California. In 2022, Governor Gavin Newsom (D) signed a bill eliminating parking requirements near transit and legalizing mixed-income multifamily housing in all commercial areas. That followed the statewide legalization of accessory dwelling units (ADUs) in 2016, and a 2021 measure allowing property owners to split a single-family home or lot into duplexes or fourplexes. Opponents have vowed to reverse that law through a ballot initiative.

Connecticut. A sweeping reform bill passed in 2021 forbids local zoning that caps the number of multifamily housing units or discriminates against lower-income residents, in a state where 90 percent of land is reserved for single-family homes as of right. The package also legalizes ADUs, caps minimum parking requirements, enforces affordable housing targets, and eliminates the terms “character,” “overcrowding of land,” and “undue concentration of population” as the legal basis for zoning regulations.

Maine. A package introduced in early 2022 would have created a state oversight board with the power to override local decisions about critical housing projects; it also would have eliminated caps on growth instituted by municipalities citing “overcrowding.” Those provisions were removed, leaving a law that allows ADUs on land zoned for single-family homes.

Maryland. A 2020 bill to increase housing density in higher-income areas that have a concentration of jobs and access to transit failed to progress, as did another measure requiring municipalities to allow ADUs. Baltimore has considered ending single-family-only zoning on its own.

Massachusetts. Under the MBTA Communities law passed in 2021 and signed by Governor Charlie Baker (R), multifamily housing at a density of 15 units per acre must be allowed by right near transit stations, or state funding for infrastructure and other projects will be withheld. Several communities have challenged the policy, and some have indicated willingness to forgo the funding rather than comply.

Montana. In late 2022, a housing task force appointed by Governor Greg Gianforte (R) recommended opening areas zoned for single-family homes to duplexes, triplexes, and fourplexes, and overhauling other restrictive local zoning regulations. The head of the organization representing Montana cities and towns called the effort “straight out of California.” The legislature is expected to consider related proposals this year.

Nebraska. A bill introduced in 2020 and intended to ban single-family-only zoning and allow fourplexes was replaced by a measure that requires only that cities and towns show they are working toward affordable housing.

North Carolina. Bipartisan legislation in 2021 called for allowing duplexes, triplexes, fourplexes, and townhomes in any residential zoning district with water and sewer service, and allowing ADUs. That proposal stalled after opposition from local jurisdictions.

Oregon. The first state in the country to ban single-family-only zoning, Oregon enacted a law in 2019 that requires most cities with populations over 1,000 to allow duplexes, and requires municipalities of 25,000 or more to allow townhouses, triplexes, and fourplexes.

Utah. A measure passed in 2022 leverages state funding for local zoning reform that makes it easier to build middle-income housing and transit-oriented development. In late 2022, the state legislature was also considering withholding state funds for communities that lack a housing master plan, and overriding local zoning and hearings processes to allow landowners to build affordable housing.

Virginia. Governor Glenn Youngkin (R), who has been critical of NIMBYism, released a plan in November that recommends linking state funding to local housing plans and investigating comprehensive zoning reform.

Washington. Legislation under consideration would allow greater density at transit stations and permit two-, three-, and four-family homes in areas now zoned for single-family homes.


Anthony Flint is a senior fellow at the Lincoln Institute, host of the Land Matters podcast, and a contributing editor to Land Lines.

Image: Accessory dwelling unit in Seattle. Credit: Sightline Institute via Flickr CC BY 2.0.