Manhattan · Unit 4B · BBL 1000291213

21 South William Street, Unit 4B

New York, NY 10004 · Manhattan

Also written as: 21 S William St Apt 4B · 21 South William Street #4B · 21 S William St Unit 4B

Part of 21 South William Street Condominium

Owner of record: BOSHNACK, ROBERT

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

Assessment (FY2027)

  • Assessed value: $69,652
  • Market value: $154,782
  • Tax class: 2

Building

  • Office (O4)
  • Built 1928, altered 2004
  • 0 residential / 96 units
  • 34 floors
  • Zoning: C5-5
  • Lot area: 26,068 sf
  • Building area: 661,283 sf
  • Flood zone: 1

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-4b-1000291213

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