1230 Madison Avenue

This building is described almost everywhere — including, until this revision, on this page — as a condominium. It is not.

The public record is unambiguous on the point, and it is worth showing the work, because the mistake changes what a buyer is actually purchasing:

• The Department of Finance carries the property in building class D4 — elevator cooperative, not in any condominium class.
• The property sits on a conventional tax lot (Manhattan block 1500, lot 54). A condominium is subdivided into individual unit tax lots numbered from 1001 upward, and each apartment is separately assessed and billed. No such unit lots exist here. The whole building is assessed as a single parcel, which is how cooperatives are taxed and is structurally impossible for a condominium.
• Recorded transfers of the individual apartments are filed as single residential cooperative unit transactions — transfers of shares with an assignment of proprietary lease, not deeds. The recorded apartment transfers of early 2025 were filed this way.

So the entire "no board, condo flexibility" argument that circulates about this building — and that this page previously made — is wrong. A purchase here goes to a cooperative board, subject to a board package, financial review, and interview. Financing terms, sublet policy, pied-à-terre and trust or LLC purchases, and any flip tax are all governed by the co-op's own rules, which are not published and must come from the managing agent before an offer.

That correction is not a knock on the building. It is the most interesting thing about it.

The exterior is the point. Rather than the glass curtain wall that defines most new Manhattan luxury construction, the building is clad in a limestone-forward classical composition by Robert A.M. Stern Architects, the office most closely identified with new buildings that read as pre-war. SLCE Architects served as architect of record; the Department of Buildings filings for the new building and the subsequent alterations are consistent with that division of work.

The massing sits comfortably among Carnegie Hill's masonry landmarks — the Guggenheim shares the block — with private terraces carved into select upper floors. The demolition of the prior structure and the new-building application both ran under 1230 Madison Avenue in the Department of Buildings record.

Two dimensional facts are genuinely unsettled in the public record and we state both rather than pick one: the approved new-building application describes 19 stories at 210 feet, while later alteration filings and published descriptions say 20 stories at 208 feet.

Thirteen residences is the figure in the 2018 new-building application, in city assessment records, in DOB filings since 2022, and on the project's website, which now markets thirteen full-floor, duplex and triplex homes. Fifteen was the program in the 2019–2021 alteration filings, in the cooperative plan the sponsor filed with the Attorney General in February 2020, and in the architect's 2020 description of fourteen full-floor residences and a duplex penthouse. The plan amendments that would document the change were not reviewed; recorded transfers include apartments designated as a duplex penthouse and a triplex penthouse alongside numbered floor-through residences, which is consistent with combined floors.

What is not in doubt is the shape of the stock: this is a building of very large, full-floor and multi-floor apartments, sold to a small number of households. Published figures put the average apartment at roughly 3,460 square feet. Buyers on this corridor have historically had to find space at that scale in a pre-war full-floor cooperative; here it comes with new mechanical systems, new air handling, and contemporary construction.

For a building of this size the amenity program is deliberately compact: a fitness room, an entertainment and event room, bicycle storage, and private terraces on select residences. Compare the actual amenity costs, allocation schedule, maintenance and reserves with those of specific alternatives; thirteen residences alone do not establish an appropriate program or an excessive cost burden.

The location supplies the rest. The Guggenheim is on the block, the Metropolitan Museum and Central Park are a short walk, and the Madison Avenue gallery-and-boutique corridor runs past the door. The Lexington Avenue lines and the Second Avenue subway are both within reach.

Recent sales

Recent transfers at this building, from The Roebling Research Library. Prices are the transfer amounts recorded with the NYC Department of Finance; apartment-level detail is checked against the building’s own file in The Roebling Research Library before publishing.

Market read. Most recent trades (2025) cleared a median $2,610/sf (recorded) across 2 sales. Median listing discount 9.6% from the last ask — a recurring negotiation gap worth pricing into any offer or listing strategy.

Sales sourced from NYC Department of Finance recorded transfers (BBL 1-01500-0054). Apartment-level facts (line, condition, asking-price context) curated and cross-verified in The Roebling Research Library. 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.

Underwrite this as a co-op purchase, because that is what it is. Budget for a board package, a financial disclosure, and an interview. If your purchase involves a trust, an LLC, a non-resident buyer, or a pied-à-terre use, raise it with the managing agent before you make an offer rather than after — cooperative boards can restrict these structures, and new construction does not change that.

Get the board terms in writing first. The reviewed materials did not establish the current financing ceiling, post-closing liquidity requirement, sublet policy or flip tax; obtain those terms from the operative documents and managing agent. At this price point the post-closing liquidity requirement in particular can be the binding constraint.

Confirm the apartment count and the specific unit's designation. With 13 and 15 both in the record, and with duplex and triplex penthouses in the mix, do not assume a marketing floor number corresponds to a single legal residence.

Ask what the building's financial statements show. A thirteen-unit cooperative has thirteen households funding every capital item. There is no commercial rent roll and no garage income visible in the record to cushion an assessment, and a small share count means a single major project moves everyone's maintenance. Ask for the audited financials and the reserve position.

Lead with what is actually rare. The design pedigree and the limestone facade are real, but they are not unique — Robert A.M. Stern has designed a number of Manhattan luxury buildings. Describe the new-construction cooperative on the Guggenheim block accurately, and compare that combination with current competing properties without claiming no substitute exists.

State the ownership form accurately. Describe the cooperative structure and applicable board process in marketing so prospective buyers can assess it before proceeding; a tenure error does not establish how any particular buyer will respond.

Price against the right set. Use dated sales from relevant new East Side condominiums and pre-war Carnegie Hill cooperatives, with explicit adjustments for ownership rules, size, condition, systems, services and costs. Neither tenure nor construction era establishes a governance premium, liquidity ranking or a price between those groups.

• 1122 Madison Avenue — new-construction limestone building on Madison
• 1033 Madison Avenue — Madison Avenue cooperative nearby
• 1095 Madison Avenue — a white-glove pre-war co-op
• 1040 Fifth Avenue — Fifth Avenue cooperative on Museum Mile
• 1056 Fifth Avenue — George F. Pelham Jr.'s 1951 postwar Museum Mile co-op