In 2021, Massachusetts adopted state-level legislation requiring 177 municipalities to adopt by-right multifamily zoning related to public transit infrastructure. Known as Section 3A or the MBTA Communities Act, this law responds to the state’s severe housing crisis. Massachusetts has among the highest and fastest-growing housing costs in the nation, pricing out young families and essential workers while hampering economic competitiveness. The legislation represents one of the most ambitious state-level zoning mandates in the country, requiring communities to actually change their local codes rather than simply offering incentives, and has drawn attention from other states considering similar approaches.
As of the end of 2025, all 177 municipalities should have adopted compliant zoning. CommunityScale worked with 13 of these communities, ranging in population from Lowell (114,000) to Sherborn (4,000), with a total multifamily capacity requirement of more than 32,200 units. In this article, we’ll reflect on how state-level requirements are rolled out to individual municipalities and what we learned along the way.
Lessons learned while localizing State requirements
Tailored fits
For each community, we shaped the requirements in ways that made sense locally. For some places, it was obvious where the multifamily zoning would fit into existing plans. Lowell, a regional hub, had a station area plan already in development, and the multifamily zoning requirement aligned naturally with ongoing planning goals. The city not only met but vastly exceeded the required capacity.
Other places required building consensus around a new residential framework. In Malden, a subway-served city that already allowed significant density near its transit stations, the challenge was different: the area around the Orange Line stops was already zoned for transit-oriented development, but with a commercial and mixed-use orientation. Section 3A’s requirement for by-right residential-only development without discretionary review didn’t fit neatly into that existing framework. The process involved extensive community engagement, surveys in seven languages, and careful analysis of impacts on schools, traffic, and municipal services. The result was a system of overlay subdistricts that added real new multifamily capacity while creating a mandatory mixed-use zone downtown to preserve the commercial tax base and address community concerns about affordability and development character.
Sherborn presented a different challenge altogether. In this small town of 4,000 residents, we turned over many stones before finding a clear winner: a single-parcel district that was supported by both the community and the landowner. We worked through scenarios involving the town center, various business districts, and ultimately settled on a solution that balanced state requirements with local constraints.
But not every carefully planned approach succeeded. In Duxbury, the best laid plans by a steering committee were initially voted down at Town Meeting despite months of collaborative work. Wakefield faced similar initial resistance, with their first proposal rejected at Town Meeting. However, after engaging with CommunityScale, we revised the approach to better align with community feedback in a focused district. The town successfully adopted compliant zoning on the second attempt.
Unraveling zoning changes
Several smaller communities hadn’t touched their zoning in decades. Adopting a new multifamily district necessitated digitizing zoning maps for the first time and summarizing years of piecemeal zoning updates. Some towns we worked with discovered they needed to invest in updating their entire map to properly submit compliance materials.
What started as a single overlay district became a catalyst for broader municipal modernization. This phenomenon revealed how outdated many municipal zoning systems had become. The state requirement, while focused on multifamily housing, exposed systemic gaps in how communities managed their land use regulations.
Navigating the flexibility was part of the challenge
The state’s guidelines offered flexibility in how communities could comply, but that flexibility came with its own challenges. Working with each of the 13 communities, we had to explore the nearly infinite solution space for how the new criteria could be met, which involved not only a detailed understanding of the built environment and regulatory systems, but also public (and political) input as subjective decisions created real changes to specific districts’ future.
Some communities explored form-based codes, which allowed for different design approaches but required additional technical expertise. Others used single-site districts, where the entire required capacity was concentrated on one parcel. Still others employed strategies of “wrapping the station” with multiple subdistricts, each calibrated to fit different neighborhood contexts.
State regulators also had to deal with creating regulations that fit the legislation’s language to reality on the ground. Changes about mixed-use requirements, how to deal with single-parcel districts, and how to calculate capacity on parcels with environmental constraints meant that communities and their consultants had to stay current with changes to the regulations while the deadline loomed.
The program’s lasting legacy
Looking back on this massive state-led effort, several patterns emerge. Perhaps unexpectedly, the high-profile nature of community-by-community conversation on multifamily housing brought new people and ideas into local planning processes. While this sometimes meant contentious public hearings, it also meant that more community members now understand what zoning is and are better equipped to participate in future land use decisions.
Other states have taken different approaches. Montana’s 2023 reforms allow duplexes and triplexes by right across much of the state with simpler, population-based thresholds. Massachusetts’ own Chapter 40B program, which allows developers to bypass local zoning when building affordable housing in communities below a 10% affordability threshold, offers a more direct mechanism. This new multifamily requirement attempts a middle path: requiring communities to zone for housing, but leaving design standards, exact locations, and much of the implementation in local hands. That flexibility makes the program more palatable to municipalities but also more complex to calculate, communicate, and ultimately achieve.
What’s next?
Other states are rolling out similar programs. Arizona’s HB 2721 (2024) requires cities with populations over 75,000 to allow duplexes through fourplexes within a mile of downtowns by 2026. Colorado passed a package of six housing bills in 2024, including HB 1313, which requires transit-oriented density near rail and bus stops, and HB 1152, which legalizes ADUs statewide. Maine’s LD 2003 (2022) effectively ended single-family-only zoning statewide and requires communities to allow up to four units in designated growth areas. Rhode Island has passed nearly 50 housing-related laws since 2021, streamlining permitting, requiring municipalities to allow diverse housing types, and mandating electronic development review. Montana’s 2023 reforms (sometimes called the “Montana Miracle”) allow duplexes and triplexes by right across much of the state with simpler population-based thresholds. Connecticut, Oregon, Washington, and Vermont have also enacted statewide zoning changes targeting housing supply.
When localizing these requirements, the lessons from Massachusetts will be valuable. Success depends on understanding local context, building genuine community support, staying nimble as regulations evolve, and being honest about what compliance will actually achieve.
CommunityScale will partner with you to navigate these challenges, bringing our experience from more than a dozen unique Massachusetts communities to your state’s requirements. We know that state mandates are just the starting point; the real work is in making them fit your community’s vision for the future.
