DOB Complaints: Illegal Apartments, No-Permit Work and More

New Yorkers filed 103,068 complaints with the Department of Buildings (DOB) through 311 in 2025. The single most common descriptor was an illegal conversion: a report that a residential, commercial or industrial space was converted illegally (311 does not record how). There were 15,134 of those, about 14.7% of all DOB complaints, and 54.0% came from Queens.

What people report

311 sorts DOB complaints into types and more specific descriptors. After illegal residential conversions (14,905), the most common descriptors in 2025 were elevator problems in buildings with a single elevator, construction with no building permit (8,873), and elevator problems in buildings with several elevators. Another 5,645 complaints reported work without a permit in an occupied apartment building. Add the complaints about work beyond approved plans (2,994) and work despite a stop-work order (2,163) and these four permit-related descriptors total 19,675, or 19.1% of everything sent to DOB.

The labels are 311's own. For example, "Elevator: only elevator in building" is our shorthand for the 311 descriptor "Elevator - Single Device On Property/No Alternate Service," which separates buildings where a broken elevator leaves no alternative.

Illegal conversions: the trend

Illegal conversion complaints fell from 19,749 in 2018 to 11,229 in 2020, the first year of the COVID-19 pandemic, when all DOB complaints dropped. They rose every year after that to 15,766 in 2024, then dipped slightly to 15,134 in 2025. Almost all (98.5% in 2025) concern residential buildings or space; a few hundred a year concern commercial or manufacturing space.

Over the same years, total DOB complaints went from 137,889 in 2018 to 103,068 in 2025, so illegal conversions have stayed between about 13% and 15% of the total each year. A complaint is an allegation. It does not mean an inspector found an illegal unit, and the data cannot tell us how many illegal apartments exist.

Where: Queens dominates

Queens had 8,167 illegal conversion complaints in 2025, more than Brooklyn, the Bronx, Manhattan and Staten Island combined. The six community boards with the most such complaints are all in Queens. Queens 10 stands out: 2,792 of its 4,481 DOB complaints (62.3%) were about illegal conversions, and it also had the most DOB complaints of any board overall.

Boards with the most complaints of every kind look different. Bronx 4 and Brooklyn 1 are in the overall top five but have relatively few illegal conversion complaints, which suggests other complaint types, such as elevators or construction, drive their totals.

Status

By 2026-10-12, 14,592 of the 2025 illegal conversion complaints (96.4%) were marked closed in 311. Closed means the request is no longer open in 311. The status alone does not say whether an inspector found an illegal unit, found nothing or could not get in.

Limits of this data

• These are 311 requests assigned to DOB. Complaints DOB staff enter directly, or that arrive another way, may not appear.
• DOB's own DOB Complaints Received dataset was checked first, but on 2026-10-12 it held no complaints entered after May 2022, so we used 311 data instead.
• Requests are reports, not findings. One condition can produce several complaints, and some areas report more than others.
• Board counts are raw totals, not adjusted for population or number of buildings. 338 2025 requests had no community board.
• 2018 and 2019 come from the older 311 dataset (76ig-c548); 2020 onward from the current one.