Office building with commercial space · Flatiron, Manhattan
Spero Building
19 West 21st Street, New York, NY 10010
The Spero Building (19 West 21st Street) is a 12-floor office building with commercial space in Flatiron, Manhattan, built in 1908, with about 103,000 square feet of office space according to city records.
Also at 19-27 West 21st Street.
- Office space
- 103K SF
- Floors
- 12
- Year built
- 1908
- Zoning
- C6-4A
The 36th largest of the 90 office buildings we track in Flatiron. Compare it with 6 neighbors
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Compared with its neighbors
How the Spero Building compares
Next to the 6 nearest large office buildings, all within a 1 minute walk, the Spero Building ranks 3rd of 7 by office floor area. It went up in 1908; the median neighbor dates from 1907. Its estimated property tax, about $10.78 a square foot of floor area before abatements, is above the neighbors' median of $10.16.
| Building | Office space | Floors | Built | Tax / SF |
|---|---|---|---|---|
| Spero Building, 19 West 21st Street | 103K SF | 12 | 1908 | $10.78 |
| 15 West 21st Street | 117K SF | 12 | 1910 | $10.52 |
| Taylor Building, 20 West 22nd Street | 144K SF | 16 | 1911 | $13.29 |
| 22 West 21st Street | 93K SF | 12 | 1908 | $12.10 |
| 18 West 21st Street | 49K SF | 11 | 1907 | $9.46 |
| 30 West 21st Street | 58K SF | 15 | 1907 | $7.99 |
| 12 West 21st Street | 50K SF | 12 | 1907 | $9.81 |
Sources: NYC Department of City Planning, PLUTO 26v2 for size, floors and year built; NYC Department of Finance 2026/27 roll for tax (taxable value times the class rate, before abatements, over the whole floor area). Large means at least 35,000 SF of the building's main use. Walking times are straight-line estimates.
NYC tax lot records
Building facts
- Building name
- Spero Building
- Other address
- 19-27 West 21st Street
- ZIP code
- 10010
- Building type
- Office building with commercial space (city class O6)
- Total floor area
- 113,284 SF
- Commercial floor area
- 113,284 SF
- Office
- 103,384 SF
- Retail
- 9,900 SF
- Height
- 12 floors
- Average floor
- About 9,400 SF (floor area divided by floors)
- Year built
- 1908
- Lot area
- 10,377 SF
- Zoning district
- C6-4A
- Built FAR
- 10.92
- Max commercial FAR
- 10
- Historic district
- Ladies' Mile Historic District
- Tax lot (BBL)
- 1008230024
Nearest subway
- 23 St
- 23 St
- 23 St-Baruch College
Source: NYC Department of City Planning, PLUTO 26v2, pulled 2026-10-16; addresses from the Property Address Directory (PAD) 26b; building name from the NYC Landmarks Preservation Commission (below); subway stations from the MTA Subway Stations dataset, pulled 2026-10-16. Floor areas are the city's estimates for the whole building, not available space. Walking times are straight-line estimates. How we build these pages. Something wrong on this page? Tell us.
NYC storefront registry (Local Law 157)
Storefronts and vacancy
Owners registered 2 storefronts at the Spero Building for December 31, 2025, the newest annual filing the city has published, and none stood vacant that day.
- Storefronts registered for December 31, 2025
- 2
- Vacant that day
- 0
- Share vacant across Flatiron
- 11.8%
- Share vacant along West 21st Street
- 5.9%
- Share vacant citywide
- 9.2%
Vacant on December 31, by year
Need a storefront in Flatiron? Get matchedNYC storefront vacancy report
Source: NYC Department of Finance, Storefronts Reported Vacant or Not (Local Law 157), annual filings for 2019 to 2025, pulled 2026-10-16. Owners of buildings with ground- or second-floor storefronts register each one every year with its status on December 31; counts are by tax lot, as the owners filed them. The 2025 filing was due June 1, 2026, so a storefront vacant then may have been leased since. A vacant storefront is not always on the market, and none here is listed on Leasemark unless it shows above.
NYC Department of Finance records
Owner, property tax and assessed value
The Department of Finance lists FIFTH PARTNERS LLC as the owner of record. For tax year 2026/27 the city values the Spero Building at $25.9 million and assesses it at $11.7 million. After phase-ins and exemptions its taxable value is $11.3 million; at the Class 4 rate of 10.848% (tax year 2025/26, the latest rate the Department of Finance lists) that comes to about $1.22 million a year before abatements, roughly $10.78 per square foot of floor area. Commercial leases here often pass a tenant's share of tax increases over a base year through as additional rent.
- Owner of record
- FIFTH PARTNERS LLC
- Tax class
- Class 4 (commercial and industrial)
- City market value
- $25,898,000
- Land market value
- $9,000,000
- Assessed value
- $11,654,100
- Taxable value (phased in)
- $11,252,250
- Estimated yearly tax
- About $1.22 million
- Tax per SF of floor area
- About $10.78
City market value by tax year
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How to find who owns any NYC buildingSource: NYC Department of Finance, Property Valuation and Assessment Data (2026/27 roll; owner names as the roll records them, which cuts some long names short), pulled 2026-10-16; tax rate from the Department of Finance tax rates page, checked 2026-09-28. The estimate is the taxable value times the class rate. It leaves out abatements, payment-in-lieu-of-taxes agreements and charges, so the actual bill can differ.
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NYC Department of Buildings permits
Work permits and build-outs
The Department of Buildings issued no permits for new jobs at the Spero Building in the 12 months to October 2026; the last one was first permitted in January 2023.
- New jobs, last 12 months
- 0
- Initial permits, last 12 months
- 0
- Newest job first permitted
- January 2023
- Interior build-outs, last 24 months
- 0
New jobs by year
Build-outs across FlatironWhere NYC offices are being built out
Source: NYC Department of Buildings, DOB NOW: Build Approved Permits, pulled 2026-10-24 (permits issued through 2026-10-22). A job counts once, when its first permit is issued; renewals are not new work. A build-out groups jobs on the same floors first permitted within 120 days of each other. Costs are the estimates filed with the jobs. Jobs filed before DOB NOW (in the older BIS system) are not counted. A permit is approval to do the work; it does not say who the work is for or whether it is finished.
Landmarks Preservation Commission records
Architecture and history
The Spero Building was designed by Robert D. Kohn and built in 1907-1908 in the Art Nouveau style. It stands in the Ladies' Mile Historic District, so exterior changes and new signage go through the Landmarks Preservation Commission.
- Architect
- Robert D. Kohn
- Constructed
- 1907-1908
- Style
- Art Nouveau
- Primary material
- Limestone
- Built as
- Store and lofts
Source: NYC Landmarks Preservation Commission, Individual Landmark and Historic District Building Database on NYC Open Data, pulled 2026-10-16. A designation can cover part of a lot, such as a facade or a lobby interior.
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Questions about Spero Building
How big is the Spero Building?
The Spero Building has about 113,000 square feet of floor area in total, including 103,000 square feet of office and 10,000 square feet of retail, according to NYC PLUTO 26v2. These are the city's estimates for the whole building, not space that is available.
When was the Spero Building built?
The Landmarks Preservation Commission's building records date the Spero Building to 1907-1908, designed by Robert D. Kohn. The building is 12 floors tall.
Who designed the Spero Building?
Robert D. Kohn, according to the Landmarks Preservation Commission's building records, which list the style as Art Nouveau and its original use as store and lofts.
What is the address of the Spero Building?
The Spero Building is at 19 West 21st Street in Flatiron, Manhattan. City records list 19-27 West 21st Street on the same tax lot (BBL 1008230024). A space listed on Leasemark at any of these addresses shows up on this page.
What is the ZIP code of 19 West 21st Street?
19 West 21st Street is in ZIP code 10010, according to the city's tax lot records (NYC PLUTO 26v2) and the Department of Finance's assessment roll. The Spero Building is at 19 West 21st Street, New York, NY 10010, in Flatiron.
What is the zoning at the Spero Building?
The lot is in the C6-4A zoning district. PLUTO lists a built floor area ratio (FAR) of 10.92 and a maximum commercial FAR of 10 for this lot. It is inside the Ladies' Mile Historic District, so exterior changes go through the Landmarks Preservation Commission.
What subway station is closest to the Spero Building?
The closest subway station to the Spero Building is 23 St (the R and W trains), about 650 feet away in a straight line, roughly 3 minutes on foot. Also nearby: 23 St (the F and M trains), 3 min walk; 23 St-Baruch College (the 6 train), 6 min walk. Walking times are straight-line estimates; the street route is longer.
Who owns the Spero Building?
The NYC Department of Finance's 2026/27 assessment roll lists FIFTH PARTNERS LLC as the owner of record of the Spero Building (BBL 1008230024). Big buildings are usually held through a company set up for that one property, so the name on the roll can differ from the landlord's brand or the managing agent. Deeds and mortgages for the lot are public in ACRIS, the city's property records system.
Is there construction at the Spero Building?
The Department of Buildings issued no permits for new jobs at the Spero Building in the 12 months to October 2026; the last one was first permitted in January 2023. These are the Department of Buildings' DOB NOW work permits for tax lot 1008230024. A permit is approval to do the work; it does not say who the work is for or whether it is finished.
What are the property taxes at the Spero Building?
The Department of Finance's 2026/27 assessment roll lists a taxable value of $11.3 million for the Spero Building. At the Class 4 rate of 10.848% (tax year 2025/26, the latest rate the Department of Finance lists), that is about $1.22 million a year, roughly $10.78 per square foot of floor area, before abatements such as ICAP. The city's property tax records for BBL 1008230024 show the actual bill.
What is the assessed value of the Spero Building?
For tax year 2026/27, the NYC Department of Finance puts the market value of the Spero Building at $25.9 million ($9 million of it land) and its assessed value at $11.7 million, the 45% of market value the city assesses for Class 4 property. The city's market value rose 9% from 2022/23 ($23.8 million) to 2026/27.
Are there vacant storefronts at the Spero Building?
Owners registered 2 storefronts at the Spero Building for December 31, 2025, the newest annual filing the city has published, and none stood vacant that day. These are the owners' filings with the Department of Finance under Local Law 157, so a storefront may have come free since. Owners and brokers can list a storefront on Leasemark for free.
Is there office space for lease at the Spero Building?
No space at 19 West 21st Street is listed on Leasemark right now. Owners and brokers can list space here for free, and tenants can post a requirement to be matched when space opens up.
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Transit hubs in Flatiron
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