12 East 88th Street
12 East 88th Street, New York, NY 10128
Carnegie Hill, Upper East Side
BBL 1014997502 · BIN 1046923
- Year built
- 1931
- Type
- Condominium
- Units
- 39
- Floors
- 13
- Landmark
- No
- Pets
- Permitted with board or managing-agent consent, per the house rules on file: dogs, cats, caged birds and fish, no more than two pets per residence without further consent, no pit bulls or other dangerous animals, and pets must be carried or leashed in common areas. A pet acknowledgment is part of the purchase application
- Financing
- Condominium framework; confirm the current lender-required minimum down payment with the managing agent
Every recorded sale at this building, 2017–2026
Price-per-square-foot over time, the line- and floor-premium curves, and every recorded sale.
- Median $/sf
- $1,895
- Listing discount
- 6.7%
- Recorded sales
- 43
- On record
- 2017–2026
The blocks between Fifth and Madison in the high Eighties are among the most tightly regulated residential ground in Manhattan. The Expanded Carnegie Hill Historic District covers most of them, the zoning is R8B, and the co-ops that line the streets have been co-ops for two or three generations. 12 East 88th Street is the exception on almost every axis. It is not landmarked. It is roughly twice the bulk the current zoning would allow. And until 2017 it was not for sale at all — it was a rental building, held by a single family corporation from 1968, one of the last large unconverted rentals on the Fifth-to-Madison side streets.
That changed on March 3, 2014, when Simon Baron Development bought it for $105 million. What followed was a full-building repositioning rather than a cosmetic conversion. The sponsor filed an alteration in December 2014 to convert the building's doctors' offices — a legacy of the Carnegie Hill medical corridor — into apartments and amenity space, and then spent 2015 and 2016 combining apartments and rebuilding the building's systems: new gas, water and sanitary risers, a relocated laundry, corridor renovations on floors three through twelve, a new sprinkler and smoke- and heat-detection system, new air-conditioning, structural repairs and a façade program. Sixty-five rental apartments became thirty-nine to forty condominium residences. The offering plan was dated December 2, 2016, the condominium was organized in February 2017, and the first closing took place on August 4, 2017.
The conversion is the reason the building's apartments are the size they are. Combining 65 units into 40 within a 1931 envelope produces layouts you cannot get in new construction at this price and cannot get in the surrounding co-ops without a board's permission: full-floor and half-floor plates, two townhouse units at the base, and four penthouses at the top of a thirteen-story building on a street where new towers are effectively prohibited. The 7.97 built FAR against a 4.0 permitted FAR is the quiet reason the light and the ceiling heights work — the building simply could not be replicated.
There is a second, less advertised half to the story, and it is the most important thing a buyer at 12 East 88th needs to understand. On July 25, 2017, a matter of days before the first closing, the sponsor sold twelve residential units and twelve storage licenses in a single block transaction to an outside investor entity, which was then designated a successor sponsor under the plan and given the right to sell those units on the plan's terms. In a non-eviction conversion, a bulk sale of that shape is nearly always occupied inventory — apartments carrying tenants who did not purchase. The subsequent record is consistent with that reading: those twelve units have come back to market one at a time over the following eight years, at recorded prices dramatically below the sponsor's vacant-unit pricing in the same lines, and several have since resold at ordinary market levels once vacant. A buyer looking at a low recorded price in this building should establish, before writing an offer, whether it reflects a tenant in place or a genuine market clearing.
The last structural note is the tax posture. There is no abatement here and there never has been. The predecessor rental lot carried no exemption in any published roll, and no residential unit lot carries one today. Buyers who have underwritten abated Manhattan new-development inventory will find the monthly carry at 12 East 88th higher than the sticker suggests — and unlike an abated building, it does not step up later. It starts where it stays.
Architecture and unit composition
The site is 100 feet wide and just over 100 feet deep, and the building occupies essentially all of it across thirteen stories with roughly 80,000 square feet of residential floor area. That produces large plates: with three or four residences per typical floor, the average residence is substantially larger than the Carnegie Hill median, which is exactly what the combination program was designed to achieve.
The stack runs from two townhouse units and three ground-floor residences at the base, through lines A to F on the middle floors, to four penthouses — PH11A, PH11B, PH12A and PH14 — at the top. The line gaps through the middle of the building (2A, 4B, 6B and 8C are all absent from the recorded schedule) are the signature of a combination-driven conversion; where two lines merged, one designation disappeared. It also means that apartments in nominally the same line can differ materially in size and layout from floor to floor, so square footage and floor plans must be checked residence by residence rather than by line.
Because the building is not landmarked, exterior work here is not subject to Landmarks Preservation Commission review — a genuine and underappreciated advantage on this streetscape, where neighbours a few doors west must apply for permission to change a window. It also means the façade program is entirely the condominium's own economic decision. DOB filings record façade repairs and structural work in 2016 during the conversion; a buyer should ask for the current Local Law 11 cycle status and the engineer's report regardless.
Building operations
The condominium runs with union staff under a 32BJ collective bargaining agreement, and the amenity program was created during the conversion out of the former medical office space at the base. The building changed managing agents in 2018, from the firm the sponsor installed at closing to the firm that has run it since.
The audited financial statements on file for the condominium's first partial year show a building capitalized the way a well-structured conversion should be: roughly $1.45 million held in reserve money-market accounts at year-end against modest operating cash, funded by the sponsor's 3 percent-of-sales-price reserve contribution and by purchaser working-capital contributions. Two features of that statement deserve a buyer's attention. First, the condominium had not commissioned a reserve study or adopted a funding plan for future major repairs and replacements — the auditor noted the omission expressly. Second, the sponsor submitted a schedule of claimed costs of $658,949 for expenses paid on behalf of the condominium, of which the board recorded $393,143 after reviewing supporting documentation, leaving an unresolved balance the sponsor could pursue as a credit.
Both of those are 2017 facts about a building that is now nine years into operation, and neither is a red flag on its own. They are, however, precisely the questions to put to the managing agent: has a reserve study been done since, what is the current reserve position, has the sponsor claim been resolved, and are there any assessments in place or contemplated. Ask for the most recent audited statement and the current year's budget, not the conversion-era documents.
Policy framework
Ownership form: Condominium. Transfers proceed through the board's right of first refusal. Closing timelines run on condominium rather than cooperative terms.
Purchase application: Notwithstanding the right-of-first-refusal structure, the board reviews a substantial package. Per the application requirements on file, purchasers submit a financial statement with supporting bank, investment and retirement statements, personal, professional and bank references, a consumer-report authorization, a loan commitment letter where financing, income verification with pay stubs or a CPA letter, emergency contact information, the executed contract of sale, and signed acknowledgments including house rules, pet, window-guard and lead-paint disclosures. Entity purchasers add the certificate of incorporation, corporate resolution and operating agreement for an LLC, or the trust agreement for a trust, or the certificate of formation and partnership agreement for a partnership.
Pets: Permitted with consent, capped at two per residence, with the usual carrying-and-leashing rule in common areas and an express prohibition on pit bulls and other dangerous animals.
House rules of practical consequence: at least 80 percent of each residence's floor area (excluding kitchens, baths, closets and foyers) must be carpeted or otherwise sound-attenuated unless the board authorizes otherwise; no music or amplified sound between 11:00 p.m. and 7:00 a.m. if it disturbs neighbours; construction and renovation work only on weekdays between 8:00 a.m. and 5:00 p.m.; no roof access; no barbecuing except in areas the board designates; terrace planters limited by weight and requiring board consent above a defined size; and board approval required for any air-conditioning or ventilation installation.
Fees: the application, financing, document-retention and consumer-report fees, and the move-in and move-out deposits and fees, are set out under "At a glance" above and should be confirmed as current with the managing agent.
Flip tax or resale contribution: Not documented in the records reviewed for this profile. Confirm in writing with the managing agent before contract.
Local Law 97
- 2024–2029 annual penalty
- $0 (under cap)
- 2030–2034 annual penalty
- $13,206/yr
- Per unit / month range
- $0 – $29
Source: NYC LL84 benchmarking and PLUTO · The Roebling Research Library. City record last verified September 2026.
See full Local Law 97 analysis — emissions history, scenarios, methodology →Facade safety — Local Law 11
The latest available FISP filing classified the facade as Safe — no repairs were required at that inspection. Facade inspections run on a fixed five-year cycle; future inspection, repair, and any assessment decisions remain building-specific.
How to read this, and where it comes from
QEWI = Qualified Exterior Wall Inspector — the licensed engineer the city requires to sign the report (the independent expert, not the managing agent).
Penalties shown are amounts DOB assessed against filings on record across 2005–10 to 2025–30. The FISP dataset does not record whether they were paid, contested or remain open, so treat the figure as history rather than a current balance and confirm the building’s standing with the managing agent.
Source: NYC DOB facade filings (FISP) · The Roebling Research Library. City record last verified September 2026.
Recent sales
Carnegie Hill trades on a narrow set of variables — light, ceiling height, layout, and whether the building is a prewar co-op or something else. 12 East 88th is something else: a 1931 building with prewar proportions and condominium ownership, on a street of co-ops, without an abatement and without landmark constraint. That combination has a specific buyer — one who wants prewar scale but not a board, and who is willing to carry a full tax bill for the flexibility.
Pricing at the building has two distinct populations, and they should never be blended. Sponsor sales of vacant, renovated residences between 2017 and 2021 cleared at Carnegie Hill condominium levels, with the upper floors and penthouses at a substantial premium to the lower stack. The twelve units that went out in the 2017 bulk transaction have traded at a fraction of those levels while occupied, and at market levels once vacant. Any comparable analysis in this building that does not separate occupied-unit transfers from vacant-unit sales will produce a number that is wrong by a wide margin. Indexed to the last complete year, Carnegie Hill condominium pricing continues to reward renovated full-floor and half-floor layouts and to discount the lower stack; in this building, occupancy status matters more than either.
Unit-level transaction history is maintained in The Roebling Research Library and shared with clients during diligence.
Recent closings at this building, curated by The Roebling Team research desk. 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.
| Date | Unit | Apartment | Price | PPSF | vs. Ask |
|---|---|---|---|---|---|
| Jul 28, 2026 | 3B | 1 BR · 1 BA · 868 sf | $1,100,000 | $1,267/sf | off-mkt |
| Jul 22, 2026 | PH14 | 3,435 sf | $7,557,633 | $2,200/sf | off-mkt |
| Jul 13, 2026 | 8A | 4 BR · 4.5 BA · 3,000 sf | $6,500,000 | $2,167/sf | +0.0% |
| Apr 7, 2026 | 3C | 3 BR · 2,824 sf | $5,650,000 | $2,001/sf | off-mkt |
| Mar 9, 2026 | 2D | 2 BR · 2 BA · 1,449 sf | $2,300,000 | $1,587/sf | -8.0% |
| Nov 17, 2025 | PH11 | 3 BR · 3.5 BA · 2,192 sf | $4,325,000 | $1,973/sf | -13.5% |
| Nov 14, 2025 | PH11B | 2,192 sf | $4,443,262 | $2,027/sf | off-mkt |
| Feb 25, 2025 | 8E | 1 BR · 1 BA · 714 sf | $1,525,000 | $2,136/sf | +0.0% |
Market read. Most recent trades (2026) cleared a median $1,895/sf across 4 sales. Median listing discount 6.7% 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.
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 1-01499-7502) 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 from recorded condo declarations and offering plans.
What to know if you’re buying
Ask whether the residence is vacant. This is the first question, not the fifth. Twelve residences left the sponsor as a bulk package in July 2017 and have been resold individually since. A price that looks like a bargain in this building is usually a tenancy.
There is no abatement, and there never was. Underwrite the full tax bill from day one and compare monthlies against abated new-development inventory accordingly. The True Monthly Carrying Cost Calculator is the honest way to do that comparison.
The building is not landmarked — check the map before you assume it is. Neighbours on the same tax block sit inside the Expanded Carnegie Hill Historic District; No. 12 does not. That is an advantage for exterior work and a difference from almost everything around it.
Get the current financials, not the conversion-era ones. The first-year audit noted no reserve study and an unresolved sponsor cost claim. Ask what has happened since: reserve position, reserve study, assessments, Local Law 11 status, and whether the sponsor claim was settled.
Check the residence, not the line. The combination program means apartments carrying similar designations can differ substantially in size and plan. Verify square footage and layout against the recorded declaration for the specific unit.
What to know if you’re selling
Position against the co-ops, not against the towers. The building's argument is prewar scale with condominium flexibility on a Carnegie Hill side street — no board approval, no financing ceiling, trust and entity ownership accommodated. That is a real differentiator to the buyer who has just been turned down or slowed down by a co-op board.
Separate your comparables before the buyer's broker does. If occupied-unit transfers are sitting in the building's recorded history alongside your line, explain them proactively. Left unexplained, they become a negotiating tool.
Lead with the layout. A combined full-floor or half-floor plate in a 1931 building at twice today's permitted bulk is the product. Floor plans and ceiling heights do more work here than the amenity list.
Have the building's paperwork assembled. The offering plan, by-laws, house rules and the most recent audited financials are on file with us and should go to serious buyers' counsel early. Diligence questions answered in the package rather than in attorney review save weeks.
Comparable buildings
- 60 East 88th Street — the block's other condominium, boutique and postmodern; the closest direct alternative for a Carnegie Hill condominium buyer.
- 2 East 88th Street — the Fifth Avenue corner co-op on the same tax block, inside the historic district; the ownership-form contrast.
- 4 East 88th Street — prewar co-op two doors west, same block, landmarked.
- 19 East 88th Street — Carnegie Hill prewar co-op directly across the street.
- 1060 Fifth Avenue — the block's Fifth Avenue anchor; the top of the local co-op market.
- 1067 Fifth Avenue — boutique Fifth Avenue co-op on the same block.
- 1010 Park Avenue — Carnegie Hill condominium, a newer-construction pricing contrast.
- 1050 Park Avenue — Carnegie Hill prewar co-op of comparable scale.
- 1088 Park Avenue — the neighbourhood's architectural co-op benchmark, one block east.
- 1130 Park Avenue — Carnegie Hill prewar co-op, larger-layout comparable.
The neighborhood
For the full corridor — architecture, schools, transit, and pricing across Upper East Side — read The Roebling Team Guide to Upper East Side.
How to read the facts on this page. Items attributed to an offering plan describe the building as it was offered at that filing — unit mix, square footage, the amenity program as planned. They are not a statement about how the building operates today. Tax and compliance figures are sourced separately to current City records and carry their own dates. House rules, staffing and fee policy can change by board resolution without any public filing: treat every policy line here as a starting point for diligence and confirm it with the managing agent.
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