A public reference
Who manages New York's co-ops and condos
Every cooperative and condominium building in New York City names a managing agent in its annual registration with the city. Read across the whole city, those filings answer a question that is otherwise asked one building at a time: how much of this market a small number of companies carry. 605 companies, 9,610 buildings and 660,367 apartments, counted from the city's own files on August 13, 2026.
What the count shows
of the apartments in the count sit with the largest 10 companies, 279,279 of 660,367. Those 10 companies are on file for 2,335 of the 9,610 buildings, so their buildings are larger than the average building on the list.
is the share held by the largest 25, which is more than half the apartments in the city's co-op and condo stock as registered. The largest 5 alone account for 29 percent.
companies, 47 percent of the 605 on the list, are on file for fewer than 5 buildings each. The median company is on file for 5 buildings. A concentrated top and a long tail of small firms are the same market, and the table below shows both at once.
is the split between cooperative and condominium buildings in the count, 4,703 co-op and 4,907 condominium. Cooperatives are usually described as the larger half of New York, and among the buildings that file with a professional managing agent the two are close to even.
The concentration, band by band
Each row is cumulative: the largest 25 includes the largest 10, which includes the largest 5. Buildings and apartments are counted separately because they answer different questions, and the gap between the two columns is itself a finding. A company at the top of this table is on file for larger buildings than a company at the foot.
| Companies | Buildings | Share of buildings | Apartments | Share of apartments |
|---|---|---|---|---|
| The largest 5 | 1,487 | 15% | 190,855 | 29% |
| The largest 10 | 2,335 | 24% | 279,279 | 42% |
| The largest 25 | 3,787 | 39% | 347,627 | 53% |
| The largest 50 | 5,079 | 53% | 396,158 | 60% |
| The largest 100 | 6,559 | 68% | 483,402 | 73% |
| The largest 250 | 8,464 | 88% | 586,945 | 89% |
| All 605 | 9,610 | 100% | 660,367 | 100% |
Percentages are rounded to whole numbers, so a column will not always add to exactly 100.
The largest single portfolio
FirstService Residential is on file for 435 cooperative and condominium buildings holding 55,285 apartments, which is 8 percent of the apartments counted here on its own. Every company, its building count and its apartment count is published in the New York City managing agent directory, and the same table is downloadable as a CSV.
How the count was made
Three files published by the City of New York on its open data portal. The Department of Housing Preservation and Development records an annual registration for every multiple dwelling of three or more units, and each registration names a managing agent; the Department of City Planning records which tax lots the city classifies as cooperative or condominium. Joining the two gives the co-op and condo buildings each company is on file for. The reading, the sources, the dates the city last updated each file and the rules that decide which companies are printed are all set out on the directory page.
Four things are worth knowing before the figures are quoted. They describe cooperative and condominium work only, so a company that also manages rental buildings is on file here for fewer buildings than it manages in total. They describe registered buildings, so a self-managed building whose registration names its own corporation is counted as self-managed and is not attributed to any company. Company names are merged where the city's file spells one company several ways, and single-building filers are held out of the published list, both of which are described in full on the directory page. And a registration is a filing rather than a live record, so a figure here is a reading taken on August 13, 2026 rather than a number that updates itself.
Using these figures
Free to read, quote, cite and link to. The three source files are published by the City of New York with no license attached to any of them, and the city asks that anyone republishing its data identify the source, the version and any modifications made. A citation to this page, which sets all three out, covers it. The underlying table is available as a CSV for anyone who would rather work with the figures directly.
If a figure here looks wrong, write to support@averbrook.com with the company name and what is wrong, and it will be checked against the city's own file and corrected.
Who publishes this
Averbrook completes condominium and cooperative lender questionnaire packages for management companies, working from the association's own documents, under the management company's own brand, in 24 to 48 business hours. The management company reviews, signs and delivers every package. If your desk is carrying questionnaire volume, how it works is the short version and the first package for a new client is free.
This count is published because the answer it holds is useful and nobody publishes it. It asks nothing of you: there is no form, no signup, and no charge.