Manhattan · BBL 1000297503

21 South William Street Condominium

New York, NY 10004 · Manhattan

Also written as: 21 S William St · 21 South William Street

Owner of record: BLOCK HALL CONDOMINIUM

Snapshot updated 2026-09-02 — open the app to refresh for live data.

Assessment (FY2027)

  • Assessed value: $0
  • Market value: $0
  • Tax class: 2

Building

  • Condominium (RM)
  • Built 1928, altered 2005
  • 31 residential / 32 units
  • 8 floors
  • Zoning: C5-5
  • Lot area: 4,377 sf
  • Building area: 23,980 sf
  • Historic district: Stone Street Historic District
  • Flood zone: 1

Units in this building (32)

Official records

ZoLa zoning · DOF property tax · Property Portal · ACRIS deeds/mortgages · DOB profile · Tax map · Map

All data sourced from NYC Department of Finance / PLUTO / ACRIS / HPD public records. https://www.sageops.ai/property/manhattan/21-south-william-street-1000297503

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