The Halsworth (645 West End Avenue)
645 West End Avenue, New York, NY 10025
- Year built
- 1912
- Type
- Cooperative
- Units
- 72
- Landmark
- Designated
Every recorded sale at this building, 2003–2026
Bedroom-by-bedroom medians, the full transfer record, and how units trade against ask.
- 2BR median
- $2M
- Recent range
- $1.6M – $2.9M
- Listing discount
- 3.7%
- Recorded transfers
- 60
The Halsworth is one of the West End Avenue prewar apartment houses produced during the avenue's transformative 1910s building boom — a 1912–1913 commission designed by the young Gaetano Ajello, who would go on to design a sequence of admired buildings up and down West End Avenue. Built for the A.C. & H.M. Hall Realty Company, the building takes its name and the "H" worked into its facade from that developer; its 300 West 92nd Street corner address places it squarely in the heart of the West End / Riverside prewar district.
What sets the building apart is the interior. The Halsworth was designed on a grand scale — an elaborate attended lobby with soaring ceilings and marble detailing — yet it holds only 72 apartments, which makes it feel intimate for its size. Inside the residences, the prewar standard is unusually high: ceiling heights of roughly 10 to 12 feet, oak-paneled and beamed dining rooms, stained-glass windows, and decorative moldings throughout. These are the period details buyers cross the avenue to find, and they survive here in unusual concentration.
Within the protected Riverside–West End Historic District, the Halsworth offers buyers authentic 1913 architecture, generous light-filled prewar layouts, a genuine rooftop amenity package, and the relative value that West End Avenue has long carried against the Central Park-facing blocks.
Architecture and unit composition
Ajello's facade is a restrained, well-proportioned prewar composition, the developer's "H" reading as a quiet historical signature across the elevations. Though the building appears massive from the street, the modest 72-unit count produces larger average floor plates than its scale would suggest.
The apartments are arranged in the classic prewar manner — gracious entry galleries, separate dining rooms in the larger lines, and well-scaled principal rooms. The signature interior features are the 10-to-12-foot ceilings, the oak-paneled and beamed dining rooms, the stained glass, and the original moldings. Finish and configuration vary apartment to apartment after a century of individual ownership and renovation.
Building operations
The Halsworth operates as a full-service pre-war cooperative with a resident superintendent. Residents enjoy a landscaped rooftop garden and a rooftop gym/exercise room — amenities richer than most prewar peers of this vintage — along with a bike room and private storage. Subtenants are permitted to use the gym and roof deck, and the bike room is available for a monthly fee billed to the shareholder.
The building's policies are well defined. A 5% flip tax on net profit is paid by the seller (with broker fee, reasonable legal fees, and city and state transfer taxes deductible from the calculation). Pets are permitted subject to board review, with an introduction letter describing the pet required. Subletting is allowed for an initial one-year term plus a single one-year renewal, with a sublet fee of 20% of monthly maintenance. Pied-à-terre purchases are considered case by case. Trusts are permitted with submission of the trust documents for co-op counsel review; LLC and corporate ownership are not allowed, and the building does not permit interest-only mortgages or guarantors. As a building within a designated historic district, exterior alterations are subject to landmark review.
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
Safe to live in today — but the last inspection flagged repairs that are due on a deadline, so facade work and its cost are coming. Whether that’s a real concern depends on the scope, the timing, and how the building plans to pay for it — reserves or an assessment — which is exactly what we’d dig into 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 →Management & transfer contacts
- Flip tax
- 5% of net profit (deductions: broker fee, legal, NYS/NYC transfer tax)
- Sublet policy
- 1 year + single 1-year extension; sublet fee 20% of monthly maintenance; no guarantors
- Pied-à-terre
- Case-by-case basis
- Notable fees
- Co-op. App fee $700; credit $125/applicant; transfer closing $300; alteration deposit $1,000-$5,000 + building service fee. No LLC/corporate, no interest-only mortgages
Recent sales
Recent transfers at this building, curated by The Roebling Team research desk. Apartment-level facts are independently verified before publishing; sale prices reflect the recorded transfer amount at the NYC Department of Finance.
| Date | Unit | Apartment | Price | PPSF | vs. Ask |
|---|---|---|---|---|---|
| Jun 22, 2026 | 2A | 3 BR · 2.5 BA | $2,865,000 | -4.3% | |
| Nov 25, 2025 | 9C | 3 BR · 3 BA · 1,500 sf | $1,600,000 | $1,067/sf | -3.0% |
| Jul 18, 2024 | 10D | 2 BR · 2.5 BA · 1,600 sf | $1,995,000 | $1,247/sf | +0.0% |
| Sep 21, 2023 | 10F | 2 BR · 2 BA · 1,600 sf | $1,995,000 | $1,247/sf | -7.2% |
| Mar 10, 2022 | 2F | 2 BR · 2 BA | $1,635,000 | -0.9% | |
| Jan 14, 2022 | 5D | 3 BR · 3 BA | $2,325,000 | +3.3% | |
| Jan 12, 2022 | 12D | 2 BR · 2.5 BA | $1,999,999 | +0.3% | |
| Dec 30, 2020 | 12C | 2 BR · 3 BA | $1,352,400 | -28.6% |
Market read. $/sf is measured on the latest sales with reliable square footage (2025): a median $1,011/sf across 1 sale. The building has traded as recently as 2026. Median listing discount 1.3% from the last ask — a recurring negotiation gap worth pricing into any offer or listing strategy.
The retrade record
Lines that have traded more than once in the public record — the building’s appreciation arc, apartment by apartment.
Other recent transfers
| Date | Unit | Price |
|---|---|---|
| Dec 9, 2009 | 9D | $1,495,000 |
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 1-01251-0062) 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; square footage on co-ops is not officially recorded, figures shown are approximate.
What to know if you’re buying
The prewar interiors are the building's selling point. Ten-to-twelve-foot ceilings, oak-paneled dining rooms, and stained glass are rare survivors — a genuine quality-of-life differentiator versus thinner postwar stock.
The rooftop amenities are a real draw. A landscaped roof garden and rooftop gym are notable for a 1913 building, and they extend to subtenants as well as owners.
The financing and ownership rules are strict. Plan for a maximum mortgage with no interest-only structures, no LLC or corporate purchases, and a board that reviews trusts and pied-à-terre requests individually.
Budget the 5% flip tax into your resale math. It is paid by the seller on net profit, with standard deductions allowed.
What to know if you’re selling
The Ajello authorship and the period interiors are marketing assets. Listing copy should foreground the architect's reputation on West End Avenue, the soaring ceilings, the oak-paneled dining rooms, and the rooftop garden and gym.
Account for the 5% net-profit flip tax. It is a meaningful seller cost; price and net-proceeds conversations should reflect it from the outset.
Pricing requires apartment-level comparable analysis. With 72 units in mixed prewar configurations, floor, exposure, and renovation history drive value more than building averages.
Closing timelines are co-op standard. Plan for roughly 6–10 weeks from contract signing to closing.
Comparable buildings
If you're considering The Halsworth, also evaluate:
- 670 West End Avenue — nearby West End Avenue prewar co-op
- 680 West End Avenue — nearby West End Avenue prewar peer
- 685 West End Avenue — nearby West End Avenue building
The Roebling Team at The Halsworth
The Roebling Team at Compass specializes in Central Park West, the Upper West Side, and the broader Park-facing Manhattan market. We publish this building profile because West End Avenue buyers and sellers deserve building-specific intelligence — architecture, board culture, transactional mechanics, and pricing at the apartment level — not generic market commentary.
If you're considering a purchase or sale at The Halsworth, a 30-minute consultation is the right starting point.
The neighborhood
For the full corridor — architecture, schools, transit, and pricing across West End Avenue — read The Roebling Team Guide to West End Avenue.
Get the full picture on this building.
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Own an apartment here? See what it would sell for.
A broker’s honest answer to three questions — what your apartment would likely sell for today, what it costs to sell, and what you’d walk away with — for your apartment at The Halsworth, in this market. Put together by a person, not an algorithm.