How Zoning Built Greater Boston: A Century of Exclusion That Still Shapes Where We Live

Historians identify roughly four eras of Greater Boston zoning that have shaped the region's housing landscape:

Early zoning often reflected Progressive Era ideals—guarding neighborhoods from factories or shoddy buildings. As towns introduced zoning between 1920 and 1937, rules were relatively straightforward. By 1920, Brockton was the first to zone; by 1937, 62 towns had followed. These plans rarely mentioned race, but they did exclude many working-class and immigrant neighborhoods by strict lot requirements. For example, some growing suburbs drew large single-family districts that implicitly kept out dense immigrant enclaves.

After World War II, almost every suburb had zoning, and many tightened rules. A 'belt' of wealthy suburbs (Weston, Dover, Carlisle, etc.) zoned for very large minimum lot sizes and effectively banned multifamily housing. Interestingly, mid-century planners still regarded small apartments as fiscally useful if they were too small for families. In essence, Boston's suburbs before the 1960s often welcomed studios for tax revenue but drew the line at family homes that might pressure schools or services.

This period saw the consolidation of exclusionary patterns. Towns like Weston and Dover established minimum lot sizes of 40,000 square feet (nearly an acre), making it financially impossible for moderate-income families to enter. Meanwhile, communities like Wellesley and Lexington maintained their exclusivity through similar restrictions.

During the Civil Rights era, many suburbs voted to freeze growth. Hundreds of town meetings adopted 'no growth' or 'low growth' policies, sharply restricting apartment construction. This surge of downzoning coincided with court-ordered school busing and a rising Black population in Boston. Local newspapers noted that residents knew exactly what they were voting for: zoning changes that would block non-white and working-class newcomers.

For a deeper examination of how this period shaped suburban segregation, see our analysis: Boston's Suburban Racism: How Exclusionary Zoning, Federal Policy, and White Flight Created Regional Segregation.

In practice, many towns simply banned multifamily housing, or allowed only age-restricted units meant for seniors. In just a few years, vast areas of the suburbs became a sea of single-family lots, a legacy that endures today.

Since the mid-1970s, zoning has remained quite restrictive, but modest changes are trickling in. Some municipalities have opened small zones to multifamily or attached housing, and an active pro-housing movement is pushing for reform. Yet even now, most land in Massachusetts remains zoned only for large single-family homes. In many towns, discretionary approvals give local boards vast power to shape or block projects.

The MBTA Communities Act represents the most significant recent attempt to address these legacy constraints, requiring 177 cities and towns to establish multi-family zoning districts. However, as of late 2024, at least 15 towns remained non-compliant, demonstrating the ongoing resistance to reform.

These historical patterns have profound effects today. Greater Boston's housing supply is still too low, and prices too high. A recent study shows that from 2020–2025 the state added nearly 98,000 homes (including 71,000 in Greater Boston). That surge even paused rent growth in 2024. But now permits are crashing—down 44% since 2021—so many fear another slowdown.

Experts note that 'the vast majority of land in Massachusetts is restricted for only constructing large, single-family homes,' which are the priciest housing form. In other words, the zoning decisions made by our grandparents still funnel growth into expensive, low-density housing.

Current data confirms longstanding patterns of segregation by income and race. Boston's neighborhoods have diversified in race, but income segregation has grown—wealthy suburbs are less affordable to middle- and lower-income families. As one analysis put it, Greater Boston's most intense segregation today is in affluent white suburbs that 'produce very little multi-family housing.' Meanwhile, inner cities and older suburbs house disproportionate shares of immigrants and people of color.

For detailed demographic analysis, explore our Massachusetts Overall Diversity Rankings 2025 and Massachusetts Demographic Sorting 2000-2024.

Although Massachusetts never legally wrote racial zoning onto the books, local land-use rules functioned to keep communities white and affluent. Large-lot rules and downzones were explicitly meant to discourage minorities, poor families, and even children from moving in. For a comprehensive analysis of how this exclusion operated, see our deep dive: Zoning as the Supply Constraint: A Policy Analysis of Housing Scarcity and Affordability in the Greater Boston Metropolitan Area.

Many suburbs adopted very strict codes during the late 1960s and 70s, and little has reversed them. As a result, areas like the MetroWest and North Shore still have vast swaths zoned for single-family homes only. Use our Neighborhood Comparison Tool to explore how different towns' zoning histories have shaped their current demographics and housing costs.

The patchwork of 150+ municipalities means even small towns can veto growth. Critics argue that hyper-local control has 'gotten out of control,' producing exclusion rather than good planning. Some see this as a state issue—after all, housing is a critical public need. The MBTA Communities Act represents an attempt to balance local preferences with regional housing needs, but implementation remains challenging.

Policymakers and advocates are brainstorming beyond traditional zoning reform. Proposed solutions include mortgage aid for first-time buyers, converting unused downtown offices into homes, and tweaking building codes to allow more units per lot. Even thousands of acres of public land could be housing sites—if local opposition can be managed.

Greater Boston's history reminds us that current challenges have deep roots. The zoning that once reinforced race and class divides is now a lightning rod for debates about affordability and equity. How do we balance local preferences with regional housing needs? Can cities and towns rewrite their zoning without erasing character? Should the state force changes to meet housing goals?

We hope this overview sparks discussion and further research. Contributors and readers alike—scholars, planners, or anyone with experience—are invited to share analysis and insights. What did we miss? Are there overlooked stories in Middlesex, Essex, Norfolk, or Suffolk counties? By understanding the historical context of our land-use rules, we can more thoughtfully consider Boston's future. This is a complex issue without easy answers, but a transparent, wide-ranging dialogue is a good start.

This blog draws on recent housing and zoning research. Key resources include Amy Dain's 'Exclusionary by Design' report on Boston-area zoning, Boston Indicators analyses of segregation and zoning, and The Boston Foundation's housing report cards. We encourage readers to explore these and other reports for a deeper dive.