SROs can vary in form depending on the building and the populations they serve. Today, they range from sleek, modern spaces for young professionals to older, subsidized buildings designed to prevent homelessness. Historically, they were just one of the countless ways in which people found housing by any means available, making SRO an umbrella term that encompasses lodging houses, rooming houses, boarding houses, residential hotels, and co-living spaces. While each of these terms carries its own historical connotations, for clarity, we will use SRO throughout this piece.

Why do SROs matter?

Greater Boston’s housing shortage is well-documented. As the region continues to attract new residents seeking educational and professional opportunities, housing production has not kept pace. However, this is not the first time Boston has faced rapid growth and an influx of new residents. Throughout its history, the city has experienced economic booms and urban expansion, though only in recent decades has this been accompanied by a surge in homelessness and housing instability.

One factor that used to help prevent homelessness was the prevalence of single-room occupancy units. By allowing individuals to rent small bedrooms with shared amenities for flexible durations, SROs provided one useful housing option, especially for single people and those who are more transient, such as new immigrants and people between jobs. These groups are among the least likely to afford long-term leases, the least willing to commit to them, and the least equipped to navigate the challenges of public housing waitlists.

The history of SROs in Boston

SROs have existed in Boston since at least the 19th century, though the concept of renting a single room in a shared unit extends back even further. Their popularity declined significantly in the latter half of the 20th century, and today, only a few thousand SRO units remain in Greater Boston. In this section, we look back at their history to see how SROs became so popular and subsequently how they faded from the public imagination, leaving an unfilled gap at the most affordable end of the housing market.

For much of the late 19th and early 20th centuries, SROs were the primary housing choice for younger workers and new arrivals to the city. In both the 1885 and 1895 censuses, more than 10 percent of Boston’s residents lived in an SRO. During this decade, Boston’s population grew from 390,000 to 496,000, while the SRO population expanded from 40,000 to a peak of 55,000. The SRO housing stock in Boston seems to have reached its highest point at the turn of the 20th century, although it is difficult to pinpoint a precise peak. By the 1920s, there were still an estimated 3,000 licensed SRO buildings providing more than 35,000 units in Boston.

SROs were concentrated in inner core neighborhoods like the South End, Beacon Hill, and the North End. The South End, in particular, became known as the Lodging-House District, where entire sections of the neighborhood were dominated by short-term rental lodging houses. The rise of SROs in the South End was driven in part by a process known as “filtering,” in which wealthier residents moved to newly developed neighborhoods like Back Bay, leaving behind townhouses that were then converted into SROs.

At the turn of the 20th century, the typical South End SRO was a converted single-family townhouse, where most common areas were repurposed as individual bedrooms for up to 19 tenants. For example, a converted single-family house of 1,742 square feet might be divided into rooms ranging from 100 to 180 square feet, with bathrooms shared between four or five tenants. Surrounding these SROs was a network of businesses tailored toward the transient clientele: laundromats, restaurants, dance halls, and bars.

According to Robert Woods, whose 1899 book, The City Wilderness, helped draw attention to daily life in SRO and settlement housing, the typical lodger were people from “the working class who are single, with a few married couples who have not yet made themselves homes; that is, they stand for the large number of unmarried persons who have to come to Boston from the distance to make their fortunes and have not yet made them.” Roughly 40 percent were foreign-born, with many others arriving from other parts of the country in search of work. Notably, they were an extremely fluid population, with many only staying in one place for a short period of time.

The broader societal acceptance of SROs coincided with the Progressive Era, a period in the late 19th and early 20th centuries of widespread political reform and an optimistic approach to solving societal problems. During this period, the South End, densely populated with SROs, also became a hub for settlement houses. These houses provided social services, education, and fostered interactions across social classes to uplift those in poverty and new immigrants, a legacy that continues today. In many ways, this was the golden age of the SRO.

The decline of SROs

Between the 1920s and 1950s, Boston’s SRO stock began to shrink due to economic and societal shifts. After World War II, government support for returning soldiers helped usher in a suburban housing construction boom and cities like Boston lost population to rapid suburbanization. This in turn reduced the demand for urban SRO housing, setting off a series of broad societal shifts that would quickly deplete Boston’s SRO housing stock. While thousands of low-income tenants still relied on SROs, few new SROs opened after the war, and those that remained were increasingly susceptible to poor maintenance and neglect. By the 1950s, the number of SRO units in Boston had dropped from 35,000 to 25,000.

Urban renewal policies and rising vacancy rates further accelerated this decline in the 1950s and 1960s. As city leaders sought to modernize neighborhoods such as Scollay Square and the West End, thousands of SROs were torn down. At this point, SROs had acquired a reputation of being blighted and unsightly. And while Boston did not crack down on their existence as harshly as some other cities—such as New York’s Housing Maintenance Code that prevented any new private SROs from being built from 1954 onward—by 1968 Boston had only 9,500 SRO units remaining.

During the real estate boom of the 1970s and 1980s, many of the remaining SROs were sold for more profitable uses, especially conversions into high-end townhouses. Their concentration in increasingly lucrative neighborhoods such as Beacon Hill and the South End contributed significantly to their resale value and convertibility.

Local zoning and regulatory changes further accelerated this decline. Boston required all SROs to be licensed, expanded minimum parking requirements, and imposed density restrictions that made new SRO development exceedingly difficult. While all this made it harder to build new SROs, it is difficult to say whether SRO construction would have occurred without these barriers. The city had changed profoundly over the course of the 20th century; neighborhoods were becoming more expensive and entrenched, local opposition to new housing was becoming more organized, and perceptions of a “good home” made any coordinated efforts to expand SROs politically unlikely.

Tragically, the resulting loss of SROs directly contributed to the emergence of widespread homelessness. While the demand for SROs had been declining for decades, thousands of Bostonians still relied on the remaining SRO stock to avert homelessness. As one 1990 report from the Citizens’ Housing and Planning Association (CHAPA) put it:

“The loss of SROs, rising rents, and deteriorating building conditions have contributed significantly to the dramatic increase in the population of single homeless people during the 1980s…. In a recent survey taken at Boston’s Pine Street Inn, over one-third of residents listed a lodging house as their prior residence.”

By 1985, Boston was down to only 3,000 SRO units. Brookline (282 licensed SRO houses in 1945 to 31 in 1990), Cambridge (153 to 27 between 1970 and 1990), and Lynn (61 to 33 between 1973 and 1990), all also saw drastic declines in SRO housing during this period. And this was part of a nationwide trend: Between the 1970s and the 1990s, the United States lost 1 million SRO units to conversions and demolitions.

The loss of Boston’s SRO housing stock throughout the 20th century wasn’t the result of a single policy decision, but rather a combination of market forces, regulatory changes , and shifting public attitudes that made these units increasingly unviable.

As suburban homeownership expanded in the mid-20th century, demand for low-cost urban rental housing declined, and SROs—once at least 50,000 units strong—were simply no longer needed at such scale. Public perception played a role as well. As concerns over housing quality and transient populations grew, policymakers responded with stricter licensing and inspection requirements for rooming houses. While well-intended, these regulations had a dual effect—improving conditions in some buildings while also pushing many of the seedier operators out of the market, in turn further reducing the active stock of SROs.

SROs today

Boston’s SROs are not completely gone. According to the City of Boston’s property records, there are 174 buildings listed as Lodging Houses containing approximately 3,539 units . This is only an estimate as some SROs could be operating without a license, and some licensed lodging houses could have features such as private bathrooms that technically make them not an SRO. According to the Mayor’s Office of Housing, an estimated 1,008 of these units are restricted to households with incomes under 30 percent of the area median income (AMI), whose rent is capped at $552/month. Important service providers, such as Caritas Communities and Haley House, operate these SROs that provide much-needed affordable housing.

Additionally, there are housing units that, while technically different from SROs, have similar characteristics, such as “co-living” units. Unlike SROs, co-living units are unlicensed and typically cater to higher-income residents. Although these units are unaffordable for many, they provide higher-income, transient professionals with housing without competing against other households, such as families, for the limited two- and three-bedroom housing options in the region.

Recently, co-living has seen a small resurgence in Boston, with new buildings like 525 LINC and 7INK marketing themselves as having many of the conveniences (furnishings, flexible contracts, social interaction) that once characterized Boston’s 20th century SROs. But they aren’t licensed as lodging houses so there is no available data on their prevalence.

There is also clearly some demand for more of this type of housing. To estimate this demand, we can take a page from the work that the Furman Center did for the city of New York, focusing on two groups: people living alone but paying too much for rent and homeless individuals. That should give us a baseline, although demand could well be demonstrably higher considering that people in other living situations, such as those living with family, roommates, or in overcrowded conditions might prefer to have a space of their own if an affordable option were available.

Approximately 72,000 households in Boston are composed of renters living alone, 46 percent of whom are considered cost-burdened—that is, spending over 30 percent of their income on housing costs. This means an estimated 33,000 single-person renter households in Boston were cost-burdened. If we combine that figure with the 5,898 people that are homeless in Boston, we can get a ballpark estimate of the potential demand for SROs in the city alone: 39,000. Add in the thousands of people in other undesirable living situations and there could be considerable demand for SRO units in Boston.

Challenges

Clearly there are regulatory, financial, and political hurdles that would have to be overcome if single-room occupancy units were to be reintroduced at any sort of scale in Boston.

Regulatory restrictions

To the best of our knowledge, there are a handful of regulatory restrictions that make the creation of an SRO difficult, but certainly not impossible.

One major hurdle is the requirement for a rooming house license, which must be approved by the Boston Licensing Board. This board has broad discretion to deny licenses if it determines that a proposed SRO could negatively impact neighbors, property values, or public safety, adding a layer of bureaucracy that can hinder development.

Minimum parking requirements present another potential obstacle. Most of Boston’s neighborhood zones mandate some level of parking, except in the densest downtown areas and developments where at least 60 percent of units are subsidized. Reducing or eliminating these requirements—whether through citywide reforms or targeted exemptions for lodging houses—would likely be necessary to facilitate SRO development.

Boston also caps allowable density through Floor Area Ratios (FAR) and minimum lot-area-per-unit requirements. FAR restricts the overall buildable area relative to the size of the lot, while minimum lot-area-per-unit standards directly cap the number of units allowed on a property. Together, these rules could effectively limit how densely units—especially smaller units like SROs—can be constructed. As a result, building new SRO-style housing typically requires special zoning approvals or variances, making these projects more complex and uncertain.

Development costs and risks surrounding SROs

One of the benefits of SROs is that their small units inevitably require less rent per unit to pencil out financially. Nonetheless, the development of new SROs can still be a financial challenge. A 2018 report from the Furman Center estimated per-unit development costs for SROs in New York City between $350,000 and $500,000, depending on location and amenities. Adjusting for inflation and increased construction costs over the past seven years, these figures are probably higher today.

Given the high cost of land and lengthy permitting and licensing processes, it would be a challenge to produce an SRO project that is able to create affordable units without significant subsidy. The Furman Center analysis estimates that SROs, with their shared amenities, can knock off upwards of $600 on a given unit’s monthly rent compared to a small studio apartment. For example, if land costs are at $200/square foot, a small studio apartment would need to be rented for $1,820/month for a developer to break even, while an SRO unit could rent for $1,040/month. Local context and calculations would alter these figures, but the upshot is that SRO units would allow developers to pencil out projects for significantly lower asking rents than most current studio and one-bedroom units.

However, this raises the issue of whether traditional lenders would finance SROs. Lenders and developers could be wary of units with shared facilities, due to perceived operational risks and unclear market demand. Buildings that mix unit sizes are generally viewed as safer investments than those consisting entirely of small units like SROs.

Public perception

In addition to the regulatory and financial hurdles for the reemergence of SROs are the political and economic stigma of such units. SROs ’ historical and even literary reputation as the last stop for the down-and-out and even criminal elements could be hard to overcome, and developers interested in pursuing SRO projects may find local opposition to be particularly fierce.

Conclusions

While SROs are not outright illegal, the combination of zoning barriers, building regulations, uncertain financial viability, and public resistance makes their path to relevance difficult. However, there remains interest in bringing back similar forms of housing in a modernized way.

One potential source of new SROs is office conversions. A recent report from Pew Housing Policy Initiative found that converting offices to SROs significantly reduces costs compared to traditional apartment conversions. While it is difficult to deduce what is possible here in Boston, a task force, such as one set up in Vancouver, could help the city weigh its options. As could an independent commission to perform a more thorough audit of the city’s legal housing environment. This audit should focus not on obstacles to building a particular type of unit, but on what prevents any type of unit for which there is a demand from being built.

Amid Boston’s prolonged housing shortage and ever-rising numbers of cost-burdened and homeless residents, it is essential to reconsider housing models that can efficiently expand affordability. Single-room occupancy (SRO) units, once a common fixture in many Boston neighborhoods, used to provide affordable housing to tens of thousands of Bostonians. SROs’ decline over the course of the 20th century resulted in a surge in homelessness that persists to this day. Given the urgent demand—with tens of thousands of single-person households in the city now struggling to afford rent—SROs warrant reconsideration. Their potential revival, particularly through strategies like office-to-housing conversions or easing of restrictions, could be a crucial piece of the city’s broader affordability strategy. Further local research is needed to assess the feasibility and impact of modern SRO development, but in the face of mounting housing pressures, dismissing this option outright would be a missed opportunity.