340 West 72nd Street (The Chatsworth Annex)
340 West 72nd Street, New York, NY 10023
Lincoln Square, Upper West Side
BBL 1011830050 · BIN 1030971
- Year built
- 1905
- Type
- Cooperative
- Floors
- 8
- Landmark
- Designated
- Flip tax
- Not documented — verify against the proprietary lease
The Chatsworth Annex is the quiet half of one of the Upper West Side's great Beaux-Arts ensembles. When George F. Johnson's Chatsworth Apartments opened in 1904 at the foot of Riverside Park — twelve stories of red brick and limestone that contemporary press ranked among the finest apartment houses on the West Side — demand was strong enough that Johnson immediately acquired the lot next door and brought back his architect, John E. Scharsmith, to add an eight-story annex. Completed in 1906 with a single sprawling apartment per floor, the Annex was conceived as the ensemble's most exclusive address; Johnson himself lived in it until his death in 1918, per the LPC designation report. The city designated the Chatsworth and Annex an individual landmark together in 1984, and the surrounding blocks were later folded into the West End-Collegiate Historic District Extension.
The two buildings have since diverged in ownership structure, and that divergence is the modern story. The main Chatsworth at 344 West 72nd Street remained a rental until HFZ Capital Group and a partner acquired it for roughly $150 million — a purchase and condominium conversion plan covered by The New York Times in 2014 — and re-launched it as a high-end condominium of roughly 81 residences. The Annex, on its own tax lot under Chatsworth Realty Corporation, operates as a cooperative per city records. The practical consequence for buyers: two addresses that read as one landmark from the street carry entirely different transfer mechanics, pricing, and board cultures, and listing aggregators routinely cross-wire their data. Building-level diligence matters more here than almost anywhere on the street.
What the Annex offers that the corridor rarely does is landmark fabric at co-op pricing on one of the Upper West Side's best blocks: Riverside Park across the street, the 72nd Street subway express stop three short blocks east, and the protected Beaux-Arts streetscape of the 1984 designation. The original one-apartment-per-floor plan also left behind unusually gracious proportions — even after subdivision, the building's larger units descend from 15-room-scale floor plates.
Architecture and unit composition
Scharsmith designed the Annex as a deliberately restrained companion: where the Chatsworth piles on cherubs, caryatids, and stag heads, the Annex works in limestone ashlar with festooned carving, round-arched ground-floor windows with cartouche keystones, and a crown-like projecting cornice that the LPC report describes bay by bay. The shared one-story entrance pavilion between the two buildings — heavily rusticated limestone with a sculpted niche, cherubs, and garland hood mold — is one of the finest small entries on the West Side. All of it is protected: the 1984 individual designation covers both buildings and their lots, and exterior work runs through LPC, as the joint facade restoration program presented in December 2022 demonstrates.
Inside, the original eight floor-through apartments have been subdivided into roughly 23 residences, so layouts vary widely — from compact units to large multi-bedroom homes that retain the deep floor plate, high ceilings, and window rhythm of the 1906 plan. Renovation quality is unit-specific, and same-line comparables are scarce; valuation here is done apartment by apartment.
Building operations
This is a small cooperative that discloses little publicly, and we treat that honestly: staffing levels, amenity specifics, and the policy stack (pets, pied-à-terre, sublets, financing limits, flip tax) should be confirmed with the managing agent at offer stage rather than assumed from aggregator listings, which intermix the Annex with the neighboring condominium's amenity package. What city records do establish: an elevator building, alterations in the 2015–2016 cycle, and an LPC-reviewed facade program in process as of late 2022 — buyers should ask how that work was funded and whether assessments attach.
Local Law 97
- 2024–2029 annual penalty
- $0 (under cap)
- 2030–2034 annual penalty
- $0 (under cap)
- Per unit / month range
- —
Facade safety — Local Law 11
The latest available filing classified the facade as Unsafe — conditions requiring corrective action, which under FISP means a protective sidewalk shed and repairs. Review the subsequent filings, the repair status, and the building’s board and financial materials — we pull the repair scope and funding picture for you.
QEWI = Qualified Exterior Wall Inspector — the licensed engineer the city requires to sign the report (the independent expert, not the managing agent). Source: NYC DOB facade filings (FISP) · The Roebling Research Library.
See the full facade history →Recent sales
Full closing history with price-per-square-foot over time, the complete retrade record, and every line that has traded.
Sales sourced from NYC Department of Finance recorded transfers (BBL 1-01183-0050) and verified listing data. Apartment-level facts (line, condition, asking-price context) curated and cross-verified by The Roebling Team research desk. Not all transactions cross-verify with ACRIS records — sponsor and LLC purchases sometimes record at stipulated values rather than market price.
What to know if you’re buying
Confirm which building you are actually buying into. The Chatsworth (344, condominium) and the Annex (340, cooperative) share a landmark designation, a block, and a Google search result — and not much else structurally. Transfer taxes, board process, financing flexibility, and pricing all differ. We verify lot, entity, and offering documents at the start of diligence, not the end.
The landmark is the asset and the constraint. The 1984 individual designation plus the historic district means window, rooftop, and facade-adjacent work runs through LPC. Review the building's alteration history and the status of the 2022 facade program before contract.
Expect thin public disclosure and underwrite accordingly. A 23-unit co-op with no marketing apparatus publishes nothing. Your attorney should review several years of financials, the facade program's funding, and the full policy stack directly from the managing agent. Run the Co-op Board Qualification Calculator before offering.
Layouts are non-fungible. Subdivided floor-throughs produce one-of-a-kind apartments. View multiple lines if possible, and price against the specific unit's proportions and light rather than a building average that barely exists.
The block is the everyday luxury. Riverside Park at the door, the 1/2/3 express at 72nd and Broadway, and the landmarked streetscape in between. For park-and-subway buyers it is one of the most efficient locations on the West Side.
What to know if you’re selling
Tell the provenance story precisely. Scharsmith, 1906, the Johnson Kahn Company, the developer who kept the best building for himself, the 1984 designation — this is among the best-documented small buildings on the West Side, and the buyer pool for landmark pre-war responds to specifics. We market from the designation report, not adjectives.
Position against the condominium next door. The Chatsworth conversion set a renovated, amenitized price ceiling for the ensemble. The Annex pitch is the same landmark, the same block, and the same bones at a meaningful per-foot discount — with co-op mechanics as the trade.
Correct the record before buyers find the noise. Aggregator pages misdate the building, mislabel its ownership type, and blend its sales with the condominium's. A well-prepared listing preempts all three with documents. We supply the LPC report and verified building data to buyers' counsel from the Research Library.
Comparable buildings
If you're considering 340 West 72nd Street, also evaluate:
- The Chatsworth (344 West 72nd Street) — the ensemble's condominium half; the renovated, amenitized alternative at a premium
- The Dorilton — the corridor's flamboyant 1900 Beaux-Arts landmark co-op at 71st and Broadway; the closest like-for-like
- The Ansonia — the Beaux-Arts icon at 73rd and Broadway; the condominium alternative in the same architectural register
- The Apthorp — Clinton & Russell's full-block 1908 landmark; the trophy-scale condominium comparison
- 137 Riverside Drive (The Clarendon) — 1906 Riverside Drive pre-war co-op of the same vintage
- 194 Riverside Drive — boutique 1901 Riverside co-op; similar scale and park orientation
- 320 West End Avenue — Candela's 1924 West End co-op; the avenue's pre-war alternative
- 11 Riverside Drive (The Schwab House) — the post-war full-service co-op alternative two blocks south
The neighborhood
For the full corridor — architecture, schools, transit, and pricing across Upper West Side — read The Roebling Team Guide to Upper West Side.
The full playbook — what goes in the package, how boards read your financials, the interview, and the timeline — plus sample cover, reference, and personal letters you can adapt.
Considering a move at 340 West 72nd Street (The Chatsworth Annex)?
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A Private Pricing Opinion — what your apartment at 340 West 72nd Street (The Chatsworth Annex) would likely sell for today, what it costs to sell, and what you’d walk away with — reviewed personally against condition, exposures, renovation quality, and the competition actually on the market.