Chapter 40B and MassHousing

About Chapter 40B

Chapter 40B, the Commonwealth's regional planning law, promotes responsible housing growth by creating a streamlined permitting process for eligible projects that utilize subsidized financing, and that meaningfully accommodate lower-income residents.

Since its passage in 1969, Chapter 40B has supported almost all affordable housing construction in Massachusetts outside of the Commonwealth's largest cities. Approximately 70,000 total units have been produced under Chapter 40B, of which over 35,000 units are restricted to households making less than 80% of the area median income (AMI).

Chapter 40B promotes regional planning solutions and new housing consistent with local and regional planning needs. The law balances the regional need for affordable housing development with local public health, public safety, design, and environmental welfare needs.

The statute allows eligible affordable housing developments to receive a comprehensive permit, even when projects require waivers of local zoning. In cities and towns that achieve certain affordable housing production goals, zoning boards of appeal may reject 40B proposals without facing an appeal from the developer, giving those communities great discretion over 40B development. Municipalities that have not achieved minimum affordable housing production thresholds have a more limited ability to reject 40B proposals.

MassHousing is one of the state's four subsidizing agencies responsible for administering development under Chapter 40B. MassHousing oversees projects financed by the Agency, as well as projects financed by the Federal Home Loan Bank of Boston, under the New England Fund (NEF) program through its private member banks.

Chapter 40B's Local Impact

Chapter 40B helps communities meet the Commonwealth’s housing needs, by providing a flexible zoning approval process that allows for the creation of new homes for individuals, families, and older adults, across a range of incomes. Comprehensive permits issued under Chapter 40B allow for streamlined approvals of mixed-income rental and homeownership housing, even when those housing proposals require waivers of local zoning. Chapter 40B does not allow developers to override state and federal statutes and regulations, including state and federal environmental protections.

Chapter 40B is the state’s regional planning statute, and the law seeks to ensure that all 351 of the Commonwealth’s cities and towns provide housing opportunities for low- and moderate-income working households and older adults.

At the same time, Chapter 40B provides ample opportunities for municipalities to control their own housing growth.

Cities and towns that achieve a minimum housing affordability threshold of 10 percent may reject 40B comprehensive permit applications without facing an appeal from the developer, giving such cities and towns great discretion over 40B proposals.

Chapter 40B regulations also extend safe harbor status to towns below the 10 percent housing affordability threshold that meet minimum annual housing growth targets. Municipalities that have planned for housing growth through an approved Housing Production Plan may achieve temporary safe harbor status under Chapter 40B with affordable housing growth of 0.5 percent per year.

In Eastern and Central Massachusetts, the median town would need to add less than 30 affordable units per year under an approved Housing Production Plan to achieve this temporary safe harbor status and maintain robust local control over Chapter 40B development.

MassHousing encourages residents and municipalities to be active participants in shaping their housing development futures by engaging in thoughtful planning for affordable housing growth. The state’s Department of Housing and Community Development provides cities and towns with a one-stop shop for planning and local technical assistance resources. Additionally, MassHousing has made $2 million available through the Planning for Housing Production Grant Program to help cities and towns implement their planning goals, and achieve safe harbor status under Chapter 40B.

MassHousing works collaboratively with the state’s other Chapter 40B subsidizing agencies to provide resources and technical assistance to municipalities with active comprehensive permit applications before their zoning boards of appeal. The Massachusetts Housing Partnership (MHP) coordinates these efforts, on behalf of the subsidizing agencies. Municipalities with active 40B proposals should consult MHP's 40B handbook for zoning boards of appeal, and contact MHP to access 40B technical assistance resources.

The nonprofit Citizens’ Housing and Planning Association maintains an active database of affordable homes for sale and rent, including affordable homes produced under Chapter 40B. Prospective homebuyers and renters may access the CHAPA database. Homebuyers may learn more about the mortgage opportunities offered by MassHousing.