Back to Block Hall building profile
21 South William StreetRecorded sales & closing prices
21 South William Street, New York, NY 10004
69 recorded closings, 2006–2023. Sortable and searchable below.
- Recorded closings
- 69
- Date range
- 2006–2023
- Median $/sf
- $1,134
- Listing discount
- 2.4%
- Monthly carry/sf
- $2.36
- Price range
- $495K – $2.4M
Change in the building’s median $/sf over each window, on a floor-adjusted basis — standardized to the building’s average floor, so it reflects price rather than which floors happened to sell. This is a different method from The Roebling Index, which publishes plain medians and applies no floor adjustment; the two are not interchangeable. Floor adjustment standardizes for floor only. It does not control for condition, size, exposure, renovation or the mix of what happened to trade. (2022 marks the rate-shock inflection.) Like-for-like repeat-sale figures to follow.
The complete recorded-sale history for Block Hall, compiled from NYC Department of Finance transfer records, with apartment-by-apartment detail from The Roebling Research Library. Across sales with a public asking price, the building carries a median listing discount of 2.4% from the last ask — a recurring negotiation gap worth pricing into any offer or listing strategy here.
Price per square foot over time
65 sales with a known square footage, by closing date.
The vertical premium
The climb in price per square foot as you rise through the building — light and views included, time-adjusted to today’s market.
Premium by line
What each line’s exposure is worth — its light, outlook, and orientation — measured against the building’s average sale.
Recent closings
The building’s 10 most recent market sales.
| Date | Unit | Apartment | Price | $/sf | vs. Ask |
|---|---|---|---|---|---|
| Sep 22, 2023 | 2D | 1 BR · 1 BA · 700 sf | $872,000 | $1,246 | -6.7% |
| Jun 13, 2023 | 3D | 1 BR · 1 BA · 745 sf | $835,000 | $1,121 | -1.8% |
| Jan 17, 2023 | 6B | 1 BR · 1 BA · 641 sf | $710,000 | $1,108 | -5.2% |
| Jul 22, 2022 | 5D | 1 BR · 1 BA · 738 sf | $875,000 | $1,186 | +0.0% |
| Aug 30, 2021 | 6D | 1 BR · 1 BA · 738 sf | $840,000 | $1,138 | +0.0% |
| Aug 12, 2021 | 2E | 1 BR · 1 BA · 698 sf | $735,000 | $1,053 | -1.9% |
| Dec 31, 2018 | 6E | 1 BR · 1 BA · 698 sf | $835,000 | $1,196 | -2.8% |
| Jul 26, 2018 | 6A | $585,000 | -14.6% | ||
| Mar 20, 2018 | 7A | 452 sf | $575,000 | $1,272 | -1.7% |
| Jan 29, 2018 | 3C | 1 BR · 1 BA · 495 sf | $675,000 | $1,364 | — |
The retrade record
Lines that have changed hands more than once in the public record — the building’s appreciation arc, apartment by apartment.
Every recorded sale
Sort any column; filter by unit or keyword. Prices are the recorded transfer amount at the NYC Department of Finance. Every sale sits in one of three states: counted in the building’s medians and trend; shown but excluded as a non-arms-length or nominal transfer; or shown and ⚑ flagged for review — a possible duplicate filing or an extreme $/sf outlier, held out of the statistics pending manual verification rather than allowed to move them.
| Apartment | ||||||
|---|---|---|---|---|---|---|
| Sep 22, 2023 | 2D | 1 BR · 1 BA | 700 | $872,000 | $1,246 | -6.7% |
| Jun 13, 2023 | 3D | 1 BR · 1 BA | 745 | $835,000 | $1,121 | -1.8% |
| Jan 17, 2023 | 6B | 1 BR · 1 BA | 641 | $710,000 | $1,108 | -5.2% |
| Jul 22, 2022 | 5D | 1 BR · 1 BA | 738 | $875,000 | $1,186 | +0.0% |
| Aug 30, 2021 | 6D | 1 BR · 1 BA | 738 | $840,000 | $1,138 | +0.0% |
| Aug 12, 2021 | 2E | 1 BR · 1 BA | 698 | $735,000 | $1,053 | -1.9% |
| Dec 31, 2018 | 6E | 1 BR · 1 BA | 698 | $835,000 | $1,196 | -2.8% |
| Jul 26, 2018 | 6A | — | $585,000 | — | -14.6% | |
| Mar 20, 2018 | 7A | 452 | $575,000 | $1,272 | -1.7% | |
| Jan 29, 2018 | 3C | 1 BR · 1 BA | 495 | $675,000 | $1,364 | — |
| Dec 15, 2017 | 4C | 1 BR · 1 BA | 529 | $750,000 | $1,418 | +0.0% |
| May 18, 2017 | 2B | 1 BR · 1 BA | 682 | $790,000 | $1,158 | +0.6% |
| Nov 14, 2016 | 6D | 1 BR · 1 BA | 738 | $800,000 | $1,084 | +3.2% |
| Nov 1, 2016 | 3B | 1 BR | 709 | $765,000 | $1,079 | — |
| Nov 1, 2016 | 6B | 1 BR | 641 | $740,000 | $1,154 | — |
| Oct 24, 2016 | 7B | 1 BR · 1 BA | 600 | $760,000 | $1,267 | -1.9% |
| Mar 3, 2016 | 3A | 1 BR | 602 | $775,000 | $1,287 | — |
| Jul 24, 2015 | 5A | 1 BR | 674 | $775,000 | $1,150 | -2.5% |
| Jul 17, 2015 | 7A | 452 | $535,000 | $1,184 | +0.0% | |
| Jun 29, 2015 | PH | 3 BRnon-market transfer (excluded from $/sf & trends) | 2,019 | $1,245,000 | — | — |
| Dec 4, 2014 | 3B | 1 BR · 1 BA | 709 | $765,000 | $1,079 | -4.3% |
| Nov 11, 2014 | 3C | 1 BR · 1 BA | 529 | $625,000 | $1,181 | -2.3% |
| Oct 22, 2014 | 6B | 1 BR · 1 BA | 641 | $740,000 | $1,154 | +0.0% |
| May 23, 2014 | 2C | 494 | $576,000 | $1,166 | — | |
| Apr 10, 2014 | 7E | 1 BR · 1 BA | — | $795,000 | — | -2.5% |
| Feb 20, 2014 | 5A | 1 BR | 621 | $673,800 | $1,085 | — |
| Nov 22, 2013 | 4B | 1 BR | 656 | $725,000 | $1,105 | — |
| Nov 1, 2013 | 7C | 1 BR | — | $650,000 | — | -6.5% |
| Sep 23, 2013 | 6E | 1 BR | 698 | $710,000 | $1,017 | -7.7% |
| Sep 13, 2013 | 4A | 602 | $660,000 | $1,096 | — | |
| Jun 12, 2013 | 2B | 1 BR · 1 BA | 715 | $695,000 | $972 | -0.6% |
| Jun 6, 2013 | 7D | 1 BR · 1 BA | 743 | $750,000 | $1,009 | -3.2% |
| Sep 20, 2011 | 6A | 463 | $495,000 | $1,069 | — | |
| May 6, 2010 | 5B | 1 BR | 700 | $585,000 | $836 | -6.4% |
| Dec 17, 2009 | 3E | 1 BR | 699 | $635,000 | $908 | -5.9% |
| Dec 11, 2008 | 5C | 495 | $725,000 | $1,465 | — | |
| Sep 15, 2008 | 3C | 1 BR · 1 BA | 495 | $565,000 | $1,141 | — |
| Jun 11, 2007 | PH | 3 BR · 2.5 BA | 1,891 | $2,400,000 | $1,269 | — |
| May 15, 2007 | 7C | 1 BR | 495 | $650,000 | $1,313 | — |
| Sep 26, 2006 | 5A | 1 BR | 621 | $590,585 | $951 | — |
| Aug 18, 2006 | 6E | 1 BR | 640 | $722,957 | $1,130 | — |
| Aug 18, 2006 | 6B | 1 BR | 641 | $605,858 | $945 | — |
| Jun 21, 2006 | 5C | 495 | $576,329 | $1,164 | — | |
| Jun 14, 2006 | 4C | 1 BR · 1 BA | 495 | $600,767 | $1,214 | — |
| Jun 14, 2006 | 2E | 1 BR · 1 BA | 640 | $717,866 | $1,122 | — |
| Jun 9, 2006 | 5E | 1 BR · 1 BA | 640 | $748,413 | $1,169 | — |
| Jun 9, 2006 | 5D | 1 BR · 1 BA | 686 | $816,636 | $1,190 | — |
| Jun 7, 2006 | 3A | 1 BR | 602 | $671,026 | $1,115 | — |
| May 31, 2006 | 3C | 1 BR · 1 BA | 495 | $548,836 | $1,109 | — |
| May 23, 2006 | 5B | 1 BR | 650 | $674,081 | $1,037 | — |
| May 22, 2006 | 6A | 463 | $518,289 | $1,119 | — | |
| May 16, 2006 | 7B | 1 BR · 1 BA | 534 | $594,658 | $1,114 | — |
| May 12, 2006 | 6C | 495 | $593,639 | $1,199 | — | |
| May 11, 2006 | 7C | 1 BR | 495 | $628,260 | $1,269 | — |
| May 9, 2006 | 4A | 602 | $585,493 | $973 | — | |
| May 8, 2006 | 7D | 1 BR · 1 BA | 692 | $857,366 | $1,239 | — |
| May 5, 2006 | 7E | 1 BR · 1 BA | 640 | $767,760 | $1,200 | — |
| May 4, 2006 | 4D | 1 BR | 642 | $760,632 | $1,185 | — |
| May 4, 2006 | 2C | 494 | $559,019 | $1,132 | — | |
| May 4, 2006 | 4E | 1 BR | 640 | $738,231 | $1,153 | — |
| May 3, 2006 | 7A | 414 | $505,986 | $1,222 | — | |
| May 3, 2006 | 6D | 1 BR · 1 BA | 687 | $860,421 | $1,252 | — |
| May 3, 2006 | 4B | 1 BR | 656 | $681,209 | $1,038 | — |
| Apr 18, 2006 | 3E | 1 BR | 640 | $748,413 | $1,169 | — |
| Apr 12, 2006 | 2B | 1 BR · 1 BA | 633 | $635,388 | $1,004 | — |
| Apr 4, 2006 | 3B | 1 BR | 656 | $660,844 | $1,007 | — |
| Mar 30, 2006 | 3D | 1 BR · 1 BA | 694 | $733,140 | $1,056 | — |
| Mar 29, 2006 | 2A | 804 | $742,304 | $923 | — | |
| Mar 28, 2006 | 2D | 1 BR · 1 BA | 642 | $722,957 | $1,126 | — |
The most recent eligible transfer recorded at this building is from 2023. Our records run through September 2026; no later qualifying sale has been recorded here, which for a small or tightly held building is common rather than a gap in the data.
Sources, exclusions and how these figures are computed
Sales sourced from NYC Department of Finance recorded transfers (BBL 1-00029-7503). 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 from recorded condo declarations and offering plans. Storage, parking, and commercial units are excluded from all figures. Floor- and line-level $/sf are time-controlled (each sale measured against the building’s going rate at the time of sale) and expressed at today’s pricing, so they isolate the floor or line premium rather than blend two decades of market movement.
Put this data to work.
Know what’s fair before you offer — we’ll show you where each line trades, the building’s discount-to-ask pattern, and where the value sits right now.
Price to the building’s real trajectory, not a guess — we’ll position your line against its true comps to maximize the outcome.