Knox Building

The Knox Building has about 616,000 square feet of floor area in total, including 592,000 square feet of office and 24,000 square feet of retail, according to NYC PLUTO 26v2. These are the city's estimates for the whole building, not space that is available.

The Landmarks Preservation Commission's building records date the Knox Building to 1901-1902, designed by John H. Duncan. The building is 29 floors tall.

John H. Duncan, according to the Landmarks Preservation Commission's building records, which list the style as Beaux-Arts and its original use as store and offices.

Yes. The Landmarks Preservation Commission designated the Knox Building an individual landmark on September 23, 1980 (LP-01091). Changes to a designated landmark, including many storefront, window and signage changes, need a permit from the Commission.

The Knox Building is at 452 Fifth Avenue in Midtown, Manhattan. City records list 442-452 Fifth Avenue and 2-4 West 40th Street on the same tax lot (BBL 1008410049). A space listed on Leasemark at any of these addresses shows up on this page.

452 Fifth Avenue is in ZIP code 10018, according to the city's tax lot records (NYC PLUTO 26v2) and the Department of Finance's assessment roll. The Knox Building is at 452 Fifth Avenue, New York, NY 10018, in Midtown.

The lot is in the C5-3 zoning district. PLUTO lists a built floor area ratio (FAR) of 18.77 and a maximum commercial FAR of 15 for this lot.

The closest subway station to the Knox Building is 5 Av (the 7, B, D, F and M trains, connected to 42 St-Bryant Pk), about 650 feet away in a straight line, roughly 3 minutes on foot. Also nearby: Grand Central-42 St (the 4, 5, 6, 7 and S trains), 4 min walk; Times Sq-42 St (the 1, 2, 3, 7, N, Q, R, W, S, A, C and E trains, connected to 42 St-Port Authority Bus Terminal), 6 min walk. Walking times are straight-line estimates; the street route is longer.

The NYC Department of Finance's 2026/27 assessment roll lists 452 FIFTH OWNERS LLC as the owner of record of the Knox Building (BBL 1008410049). 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.

Leasemark does not have the building's tenant roster, but SEC filings name companies with offices at the Knox Building. 2 public companies report the address as their principal executive office: ATHENA TECHNOLOGY ACQUISITION CORP. II (ATEK) and BOWHEAD SPECIALTY HOLDINGS INC. (BOW). One investment manager files 13F holdings reports from the address: Lombard Odier Asset Management (USA) Corp. Private companies do not file with the SEC, so the full list of tenants is longer, and a company can also report a building it owns.

The Knox Building last sold in April 2010 in a $330 million sale that covered 2 tax lots, this one among them, according to the deed recorded with the city. PROPERTY OWNER (USA) LLC sold it to 452 FIFTH OWNERS LLC. The deed is ACRIS document 2010041500321001 (BBL 1008410049) in the city's property records. A sale of the company that owns a building is not recorded as a deed, so it would not show there.

The Knox Building reported an ENERGY STAR score of 62 for calendar year 2024 in its Local Law 84 benchmarking filing. Under Local Law 33, as amended by Local Law 95 of 2019, a score of 85 or higher earns an A, 70 to 84 a B, 55 to 69 a C and under 55 a D, so 62 earns a C. The Department of Buildings assigns the grade a building posts, so the posted label can differ if a filing was corrected. Its site energy use came to 61 kBtu per square foot, 14% below the national median of 71 for a similar property. Its greenhouse gas emissions were about 4,051 metric tons of CO2e (6.19 kg per square foot).

In the 12 months to October 2026, the Department of Buildings issued first permits for 44 jobs at the Knox Building. In the last two years, interior work was permitted on 17 floors (floors 1 to 12, 21, 26, 27, 29 and 30, the cellar, the mezzanine and the sub-cellar). The newest build-out, on floors 1 and 2, the cellar and the sub-cellar, was first permitted in October 2026 (construction; filed cost estimate $698,000). These are the Department of Buildings' DOB NOW work permits for tax lot 1008410049. A permit is approval to do the work; it does not say who the work is for or whether it is finished.

The Department of Finance's 2026/27 assessment roll lists a taxable value of $154.5 million for the Knox Building. At the Class 4 rate of 10.848% (tax year 2025/26, the latest rate the Department of Finance lists), that is about $16.8 million a year, roughly $27.19 per square foot of floor area, before abatements such as ICAP. The city's property tax records for BBL 1008410049 show the actual bill.

For tax year 2026/27, the NYC Department of Finance puts the market value of the Knox Building at $343.3 million ($69.9 million of it land) and its assessed value at $154.5 million, the 45% of market value the city assesses for Class 4 property. The city's market value held steady from 2022/23 to 2026/27.

Owners registered 3 storefronts at the Knox Building for December 31, 2025, the newest annual filing the city has published, and all of them stood vacant that day. At least one storefront here has been reported vacant at the end of every year since 2023. These are the owners' filings with the Department of Finance under Local Law 157, so a storefront vacant on December 31, 2025 may have been leased since. Owners and brokers can list a storefront on Leasemark for free.

No space at 452 Fifth Avenue is listed on Leasemark right now. Nearby on Leasemark: office space for lease at 783 Madison 4th Floor in the Upper East Side (994 SF, $66.40/SF/yr). Owners and brokers can list space here for free, and tenants can post a requirement to be matched when space opens up.